{"gene":"CYP2C19","run_date":"2026-06-09T22:57:19","timeline":{"discoveries":[{"year":2003,"finding":"The CYP2C19 promoter contains a constitutive androstane receptor/pregnane X receptor binding site (CAR-RE; -1891/-1876 bp) and a glucocorticoid-responsive element (GRE; -1750/-1736 bp). Gel-shift assays showed CAR-RE binds CAR and PXR; cotransfection with hCAR, mCAR, or hPXR in HepG2 cells upregulated CYP2C19 promoter transcription, and mutation of the -1891-bp CAR-RE abolished this upregulation. Dexamethasone activated CYP2C19 promoter constructs only when cotransfected glucocorticoid receptor (GR) was present, and mutation of the GRE abolished dexamethasone activation.","method":"Gel-shift (EMSA), cotransfection/reporter assays in HepG2 cells, site-directed mutagenesis, endogenous mRNA measurement","journal":"Molecular pharmacology","confidence":"High","confidence_rationale":"Tier 1 / Strong — multiple orthogonal methods (EMSA, reporter assay, mutagenesis, endogenous mRNA), single rigorous study with functional validation at each step","pmids":["12869636"],"is_preprint":false},{"year":2010,"finding":"Estrogen receptor α (ERα) downregulates CYP2C19 expression via a newly identified ERE half-site at position -151/-147 in the CYP2C19 promoter. EMSA and chromatin immunoprecipitation confirmed ERα binding to this element; mutations in the ERE half-site significantly inhibited ligand-dependent repression. Treatment of human hepatocytes with 17β-estradiol or 17α-ethinylestradiol significantly suppressed CYP2C19 transcription. Competitive inhibition of CYP2C19 enzymatic activity by these steroids required much higher concentrations than those needed for transcriptional inhibition, indicating the primary mechanism is transcriptional.","method":"Luciferase reporter assay, EMSA, chromatin immunoprecipitation (ChIP), site-directed mutagenesis, RT-PCR in human hepatocytes, enzymatic inhibition assays in stable HEK293-CYP2C19 cells","journal":"Molecular pharmacology","confidence":"High","confidence_rationale":"Tier 1 / Strong — multiple orthogonal methods (EMSA, ChIP, mutagenesis, reporter, human hepatocytes), single rigorous study","pmids":["20675569"],"is_preprint":false},{"year":2015,"finding":"hsa-miR-29a-3p directly binds the CYP2C19 transcript coding region (predicted hybrid stability -23.3 kcal/mol) and suppresses CYP2C19 expression. RNA EMSA confirmed direct miRNA-mRNA binding; chemically induced upregulation of hsa-miR-29a-3p in HepaRG cells inversely correlated with CYP2C19 expression; inverse correlations between miR-29a-3p levels and CYP2C19 mRNA were also observed in human liver tissue samples.","method":"In silico analysis, RNA electrophoretic mobility shift assay (EMSA), qRT-PCR in HepaRG cells and human liver tissue","journal":"Biochemical pharmacology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — EMSA confirms direct binding, supported by two biological systems (cell line + human tissue), single lab","pmids":["26296572"],"is_preprint":false},{"year":2008,"finding":"CYP2C19 (bacterially expressed, purified) can 21-hydroxylate progesterone with a Vmax/Km ~17% of that of the dedicated adrenal 21-hydroxylase P450c21, and a Km of ~11 µM. CYP2C19 cannot 21-hydroxylate 17-hydroxyprogesterone. The common P450 oxidoreductase (POR) variant A503V did not substantially alter these activities.","method":"Reconstituted in vitro enzyme assay with bacterially expressed N-terminally modified C-His-tagged CYP2C19 and wild-type or A503V POR; radiolabeled substrate, Km/Vmax measurement","journal":"The Journal of clinical endocrinology and metabolism","confidence":"High","confidence_rationale":"Tier 1 / Moderate — reconstituted in vitro assay with kinetic characterization and POR variant comparison, single lab but rigorous biochemical study","pmids":["18957504"],"is_preprint":false},{"year":2004,"finding":"Active-site characterization of CYP2C19 using N-3 alkyl-substituted phenytoin, nirvanol, and barbiturate derivatives showed all are competitive inhibitors. Inhibitor stereochemistry is an important determinant of potency toward CYP2C19 (but not CYP2C9). (S)-(+)-N-3-benzylnirvanol and (R)-(-)-N-3-benzylphenobarbital are highly potent and selective CYP2C19 inhibitors (Ki < 250 nM). CYP2C19 preferentially orients N-3 substituents away from the active oxygen species (metabolizes at C-5 phenyl substituents). A validated CoMFA model for CYP2C19 active-site geometry was developed.","method":"Recombinant enzyme competitive inhibition assays (Ki determination), metabolite identification, CoMFA modeling","journal":"Archives of biochemistry and biophysics","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro inhibition kinetics with multiple substrate series, metabolite identification, and computational modeling in single rigorous study","pmids":["15288804"],"is_preprint":false},{"year":2014,"finding":"CYP2C19 activates rhein (rhubarb anthraquinone) to a reactive epoxide intermediate, as demonstrated by IC50 shift experiments (IC50 shift value 1.989). CYP2C19 is the primary metabolic enzyme for rhein. In primary rat hepatocytes, co-addition of a CYP2C19 inhibitor with rhein restored mitochondrial membrane potential and reduced AST levels, indicating CYP2C19-mediated bioactivation drives rhein hepatotoxicity.","method":"IC50 shift assay, GSH-trapping (reactive metabolite identification), primary rat hepatocyte cytotoxicity assay, mitochondrial membrane potential measurement, AST assay","journal":"Xenobiotica","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal in vitro methods (IC50 shift, GSH trapping, cell-based rescue), single lab","pmids":["25815638"],"is_preprint":false},{"year":2007,"finding":"CYP2C19 variant *19 (Ser51Gly/Ile331Val) expressed in yeast showed a 3-fold higher Km for S-mephenytoin 4'-hydroxylation compared to wild-type (CYP2C19.1B), with Vmax/Km reduced to 29–47% of wild-type, indicating decreased substrate affinity. CYP2C19 variant *18 (Arg329His/Ile331Val) showed no significant change in Km, Vmax, or Vmax/Km.","method":"Heterologous expression in yeast, enzyme kinetics (Km, Vmax determination) for S-mephenytoin 4'-hydroxylation","journal":"Xenobiotica","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — reconstituted in vitro kinetics with site-specific variants, but single lab, single substrate","pmids":["17455109"],"is_preprint":false},{"year":2007,"finding":"CYP2C19 (recombinant) can catalyze midazolam 1'-hydroxylation with a Michaelis-Menten kinetic profile, and this activity is inhibited by the selective CYP2C19 inhibitor (+)-N-3-benzylnirvanol and by S-mephenytoin. However, the contribution of CYP2C19 to midazolam 1'-hydroxylation in human liver microsomes is minor compared to CYP3A4/5, as addition of (+)-N-3-benzylnirvanol did not change intrinsic clearance in HLM preparations.","method":"Recombinant CYP2C19 enzyme assay, selective inhibitor studies, correlation analysis in human liver microsomes","journal":"Xenobiotica","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — recombinant enzyme kinetics plus HLM correlation, two orthogonal approaches, single lab","pmids":["17614006"],"is_preprint":false},{"year":2016,"finding":"CYP2C19 catalyzes stereoselective hydroxylation of tivantinib: CYP2C19 forms M5 (one hydroxylated metabolite stereoisomer) but not M4 (its stereoisomer), whereas CYP3A4/5 catalyzes both. CYP2C19 and CYP3A4/5 are the primary isoforms for tivantinib elimination.","method":"In vitro metabolism using recombinant CYP isoforms and human liver microsomes; metabolite identification and quantification","journal":"Xenobiotica","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — recombinant enzyme assays with metabolite identification demonstrating stereoselectivity, single lab","pmids":["26899628"],"is_preprint":false},{"year":2014,"finding":"The CYP2C19*10 variant protein (expressed recombinantly) shows significantly decreased catalytic activity in the biotransformation of clopidogrel and its intermediate 2-oxo-clopidogrel compared to wild-type CYP2C19.1B, establishing *10 as a partial loss-of-function allele for clopidogrel bioactivation.","method":"Recombinant protein expression, enzymatic activity assay for clopidogrel and 2-oxo-clopidogrel metabolism","journal":"Pharmacogenetics and genomics","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — direct enzymatic assay with recombinant protein, single lab, single substrate pair","pmids":["24945780"],"is_preprint":false},{"year":2014,"finding":"CYP2C19 variants (cynomolgus macaque CYP2C19 with p.Phe100Asn, p.Ala103Val, p.Ile112Leu substitutions in substrate recognition sites) showed substantially reduced catalytic activity for flurbiprofen 4'-hydroxylation, omeprazole 5-hydroxylation, and R-/S-warfarin 7-hydroxylation compared to wild-type. Kinetic analysis of Ala103Val showed it diminishes homotropic cooperativity of CYP2C19 with R-warfarin, yielding low metabolic capacity.","method":"Site-directed mutagenesis, recombinant protein expression, metabolic assays, kinetic analysis, docking simulation","journal":"Biochemical pharmacology","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — mutagenesis plus in vitro kinetics plus molecular docking, single lab, NHP ortholog","pmids":["25036290"],"is_preprint":false},{"year":2000,"finding":"Omeprazole 5-hydroxylation in Chinese liver microsomes is mediated primarily by CYP2C19 (inhibited by anti-CYP2C8/9/19 antibody; activity correlates with S-mephenytoin 4'-hydroxylation and CYP2C19 protein content), while omeprazole sulfoxidation is mediated primarily by CYP3A4 (anti-CYP3A4 antibody abolished >87% of this activity; correlated with CYP3A4 content).","method":"HPLC metabolite quantification, monoclonal antibody inhibition, Western blot, correlation analysis in human liver microsomes","journal":"Acta pharmacologica Sinica","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — antibody inhibition, immunoquantification, and correlation analysis in HLMs, single lab, multiple orthogonal approaches","pmids":["11501187"],"is_preprint":false},{"year":2003,"finding":"CYP2C19 protein and catalytic activity (S-mephenytoin 4'-hydroxylation) are detectable at 12–15% of mature values as early as 8 weeks of gestation, remain similar throughout prenatal development, do not change at birth, increase linearly over the first 5 postnatal months, and reach adult levels by 10 years of age. This ontogenic pattern differs from CYP2C9, suggesting different developmental regulatory mechanisms.","method":"Western blotting and probe substrate activity assays (mephenytoin 4'-hydroxylation) in 237 liver microsomal samples spanning 8 weeks gestation to 18 years","journal":"The Journal of pharmacology and experimental therapeutics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct protein and activity quantification across large developmental sample set, single lab, two orthogonal readouts","pmids":["14634042"],"is_preprint":false},{"year":2013,"finding":"The CYP2C19*17 allele is associated with increased hepatic CYP2C19 mRNA expression (~1.8-fold in heterozygotes, ~2.9-fold in homozygotes) and increased allelic mRNA expression ratio (~1.8-fold), confirming *17 as a cis-regulatory polymorphism enhancing CYP2C19 transcription. Additional regulatory variants beyond *17 also contribute to CYP2C19 expression variability in African American samples.","method":"qRT-PCR for mRNA quantification, allelic mRNA expression ratio (SNaPshot), enzyme activity assay (S-mephenytoin as substrate), sequencing of promoter region in human liver samples","journal":"Drug metabolism and drug interactions","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — qRT-PCR, allelic expression, and enzyme activity in human liver tissue, single lab, multiple orthogonal methods","pmids":["23412869"],"is_preprint":false},{"year":2018,"finding":"Dicloxacillin induces CYP2C19 (as well as CYP2C9 and CYP3A4) in vivo (significant reduction in omeprazole AUC; geometric mean ratio 0.33) and in vitro in primary human hepatocytes (dose-dependent increase in CYP expression and activity). This induction is mechanistically mediated through activation of the pregnane X receptor (PXR), as demonstrated by luciferase reporter assays.","method":"Randomized crossover pharmacokinetic clinical trial, primary human hepatocyte gene expression and activity assays, PXR luciferase reporter assay","journal":"British journal of clinical pharmacology","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — in vivo PK study plus mechanistic in vitro hepatocyte plus PXR reporter assay, multiple orthogonal methods","pmids":["29105855"],"is_preprint":false},{"year":2020,"finding":"Deep mutational scanning of CYP2C19 in cultured human cells (landing-pad system) measuring steady-state protein abundance for 7,660 single amino acid variants identified 36 of 121 missense variants that reduce CYP2C19 protein to <25% of wild-type. Variants at substrate recognition site 4 (SRS4) specifically reduced abundance in CYP2C19 but not CYP2C9, and joint analysis revealed double/triple mutant interactions in this region. These positions contribute to differing thermodynamic properties and substrate specificity between the two homologs.","method":"Deep mutational scanning (variant abundance by massively parallel sequencing, VAMP-seq) in cultured human cells","journal":"Genetics","confidence":"High","confidence_rationale":"Tier 1 / Strong — high-throughput functional assay measuring protein abundance of thousands of variants in human cells, confirmed critical structural features, rigorous single study","pmids":["39319420"],"is_preprint":false},{"year":2020,"finding":"CYP2C19 missense variant scanning (DMS landing-pad system) identified 36 of 121 CYP2C19 ORF missense variants with <25% of wild-type protein expression, demonstrating that a significant fraction of genomic missense variants cause loss of CYP2C19 protein.","method":"Deep mutational scanning in human cells, protein expression quantification","journal":"Clinical and translational science","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — high-throughput functional genomics, single lab, protein expression as functional readout","pmids":["32004414"],"is_preprint":false},{"year":2016,"finding":"CYP2C19 is expressed in adult human liver and in the fetal brain during neurodevelopment. Transgenic mice carrying the human CYP2C19 gene (2C19TG) showed impaired hippocampal BDNF homeostasis under stress, increased serotonin turnover reduction in hippocampus, and increased ERK1/2 and GSK3β phosphorylation, suggesting CYP2C19 modulates brain serotonin and BDNF signaling beyond classical drug metabolism.","method":"Transgenic mouse model (2C19TG), forced swim test, hippocampal BDNF and serotonin metabolite measurements, Western blot for ERK1/2 and GSK3β phosphorylation","journal":"Molecular psychiatry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple in vivo endpoints in transgenic model, single lab, several orthogonal biochemical readouts","pmids":["27895323"],"is_preprint":false},{"year":2013,"finding":"Efavirenz increases CYP2C19-mediated omeprazole metabolism (5-hydroxylation) in a CYP2C19 genotype-dependent manner: the magnitude of induction differed between CYP2C19 genotypes, and metabolic ratios of 5-hydroxylation were reduced in extensive and intermediate CYP2C19 metabolizers after efavirenz treatment, in a non-stereoselective manner. No significant association was found between CYP2B6 genotypes and this induction.","method":"Controlled pharmacokinetic clinical study in healthy subjects (n=57), CYP2C19/CYP2B6 genotyping, LC-MS/MS measurement of omeprazole enantiomers and metabolites","journal":"The pharmacogenomics journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — controlled clinical PK study with genotype stratification and stereospecific metabolite measurement, single lab","pmids":["23629159"],"is_preprint":false},{"year":2024,"finding":"CYP2C19 and CYP3A4 variants differentially affect tofacitinib metabolism: 11 CYP2C19 variants showed increased M9 (main metabolite) production and 10 showed decreased production vs. CYP2C19.1, using recombinant human enzyme systems. Myricetin inhibits tofacitinib metabolism in a non-competitive manner in rat and human liver microsomes, but competitively in CYP3A4.18 and by a mixed mechanism in CYP3A4.1 and CYP3A4.28.","method":"Recombinant human CYP2C19 and CYP3A4 variant expression system, UPLC-MS/MS metabolite quantification, enzyme kinetics in RLM and HLM","journal":"Biomedicine & pharmacotherapy","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — recombinant enzyme system with multiple variants and inhibitor kinetics, single lab","pmids":["38719708"],"is_preprint":false},{"year":2004,"finding":"CYP2C19 mediates stereoselective 4'-hydroxylation of R-mephobarbital: the mean plasma AUC of R-MPB was 92-fold greater in CYP2C19 poor metabolizers than in homozygous extensive metabolizers, and cumulative urinary 4'-hydroxy-MPB was 21-fold less in PMs. S-mephobarbital conversion to phenobarbital was not significantly affected by CYP2C19 genotype. A minor fraction of phenobarbital formation from MPB was associated with CYP2B6*6 allele.","method":"Controlled pharmacokinetic study in CYP2C19-genotyped subjects; plasma and urine drug/metabolite measurement; CYP2B6 genotyping","journal":"Pharmacogenetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — controlled human PK study with genotype stratification, single lab, clear genotype-phenotype relationship","pmids":["15284537"],"is_preprint":false},{"year":2017,"finding":"CYP2C19 poor metabolizers (with two loss-of-function alleles *2/*3) have significantly lower serum dihydroxyeicosatrienoic acid (DHET, a surrogate for epoxyeicosatrienoic acids/EETs) levels compared to non-PMs in patients with microvascular angina, suggesting CYP2C19 has epoxygenase activity toward arachidonic acid producing EETs in vivo.","method":"CYP2C19 genotyping, serum DHET measurement (EET metabolite proxy) in microvascular angina patients and controls","journal":"International journal of cardiology. Heart & vasculature","confidence":"Low","confidence_rationale":"Tier 3 / Weak — indirect in vivo metabolite measurement, no direct enzyme assay for EET production, single observational study","pmids":["28616567"],"is_preprint":false}],"current_model":"CYP2C19 is a hepatic (and fetal brain-expressed) cytochrome P450 enzyme whose transcription is activated by CAR/PXR via a promoter CAR-RE element and by glucocorticoid receptor via a GRE, downregulated by ERα via a promoter ERE half-site, and post-transcriptionally suppressed by hsa-miR-29a-3p; the *17 allele acts as a cis-regulatory variant that increases mRNA ~2-fold, while *2 and other loss-of-function alleles reduce or abolish the enzyme; the enzyme stereoselectively hydroxylates substrates including S-mephenytoin, omeprazole, clopidogrel (to active metabolite), mephobarbital, tivantinib, and progesterone (21-hydroxylation), with active-site geometry that is sensitive to inhibitor stereochemistry and is distinct from the closely related CYP2C9."},"narrative":{"mechanistic_narrative":"CYP2C19 is a hepatic cytochrome P450 monooxygenase that performs stereoselective oxidative metabolism of a broad range of clinical drugs and endogenous substrates [PMID:15288804, PMID:26899628]. Its transcription is governed by a network of nuclear receptors acting at defined promoter elements: CAR and PXR bind a CAR-RE (-1891/-1876) and the glucocorticoid receptor binds a GRE (-1750/-1736) to upregulate expression, while ERα binds an ERE half-site (-151/-147) to mediate ligand-dependent repression [PMID:12869636, PMID:20675569]; PXR activation also underlies xenobiotic induction by agents such as dicloxacillin [PMID:29105855]. Expression is further constrained post-transcriptionally by direct binding of hsa-miR-29a-3p to the transcript coding region [PMID:26296572], and the cis-regulatory *17 allele increases hepatic mRNA roughly two- to threefold [PMID:23412869]. Catalytically, CYP2C19 hydroxylates S-mephenytoin, omeprazole (5-hydroxylation), R-mephobarbital, tivantinib, and clopidogrel, and bioactivates compounds including rhein to a hepatotoxic reactive epoxide [PMID:11501187, PMID:15284537, PMID:26899628, PMID:24945780, PMID:25815638]; it also possesses minor capacity for progesterone 21-hydroxylation [PMID:18957504]. Active-site geometry is sensitive to inhibitor stereochemistry and is distinguished from the closely related CYP2C9 by substrate recognition site residues, particularly SRS4, that determine both protein stability and substrate specificity [PMID:15288804, PMID:39319420]. Loss-of-function and altered-function missense variants, including *10, *18, *19, reduce catalytic activity or protein abundance, while a substantial fraction of genomic missense variants destabilize the protein [PMID:17455109, PMID:24945780, PMID:39319420, PMID:32004414]. Beyond drug metabolism, CYP2C19 is expressed in fetal brain and, in a humanized transgenic model, modulates hippocampal BDNF and serotonin signaling [PMID:27895323].","teleology":[{"year":2000,"claim":"Establishing which P450 isoform drives a clinically important metabolic reaction was needed to assign drug-handling responsibility; this defined CYP2C19 as the principal omeprazole 5-hydroxylase distinct from CYP3A4-mediated sulfoxidation.","evidence":"Antibody inhibition, immunoquantification, and correlation analysis in human liver microsomes","pmids":["11501187"],"confidence":"Medium","gaps":["Does not resolve atomic active-site determinants of regioselectivity","Population-specific to Chinese liver samples"]},{"year":2003,"claim":"How CYP2C19 transcription is controlled was unknown; identification of a CAR/PXR-binding CAR-RE and a GR-responsive GRE in the promoter established receptor-mediated transcriptional induction.","evidence":"EMSA, reporter assays, and site-directed mutagenesis in HepG2 cells with endogenous mRNA measurement","pmids":["12869636"],"confidence":"High","gaps":["Does not quantify relative contribution of each receptor in vivo","Endogenous chromatin occupancy not tested by ChIP"]},{"year":2003,"claim":"Whether CYP2C19 is developmentally regulated like its paralog was open; ontogeny profiling showed a distinct expression trajectory from fetal life to adulthood, implying separate developmental control from CYP2C9.","evidence":"Western blotting and mephenytoin 4'-hydroxylation activity across 237 liver microsomal samples","pmids":["14634042"],"confidence":"Medium","gaps":["Regulatory factors driving the developmental pattern not identified","Brain ontogeny not assessed"]},{"year":2004,"claim":"The structural basis of CYP2C19 substrate/inhibitor selectivity was undefined; inhibitor stereochemistry studies and CoMFA modeling defined an active-site geometry that orients N-3 substituents and distinguishes CYP2C19 from CYP2C9.","evidence":"Recombinant enzyme competitive inhibition kinetics, metabolite identification, and CoMFA modeling","pmids":["15288804"],"confidence":"High","gaps":["No experimental crystal structure presented","Model derived from limited inhibitor chemotypes"]},{"year":2004,"claim":"Assigning the in vivo stereoselective metabolism of mephobarbital clarified CYP2C19's enantiomer-specific role; PM genotypes showed dramatically elevated R-mephobarbital exposure while S-conversion was genotype-independent.","evidence":"Controlled human PK study with CYP2C19 genotyping and plasma/urine metabolite measurement","pmids":["15284537"],"confidence":"Medium","gaps":["Mechanistic basis of enantiomer discrimination not structurally resolved","Limited to one substrate"]},{"year":2007,"claim":"Defining the functional consequences of natural variants was needed for pharmacogenetic interpretation; kinetic characterization showed *19 reduces substrate affinity for S-mephenytoin while *18 is functionally neutral.","evidence":"Heterologous yeast expression and Km/Vmax kinetics for S-mephenytoin 4'-hydroxylation","pmids":["17455109"],"confidence":"Medium","gaps":["Single substrate tested","Yeast expression may not reflect human hepatic context"]},{"year":2007,"claim":"Whether CYP2C19 contributes meaningfully to midazolam metabolism was tested; recombinant enzyme catalyzed 1'-hydroxylation but inhibitor studies showed its hepatic contribution is minor relative to CYP3A4/5.","evidence":"Recombinant enzyme kinetics with selective inhibitor and HLM correlation analysis","pmids":["17614006"],"confidence":"Medium","gaps":["Does not address physiological relevance in special populations","Single-lab HLM correlation"]},{"year":2008,"claim":"Whether CYP2C19 acts on endogenous steroids was unresolved; reconstituted assays showed it can 21-hydroxylate progesterone but not 17-hydroxyprogesterone, defining a restricted endogenous substrate capacity.","evidence":"Reconstituted in vitro assay with purified CYP2C19 and POR, radiolabeled substrate kinetics","pmids":["18957504"],"confidence":"High","gaps":["Physiological significance of progesterone 21-hydroxylation in vivo unknown","Activity is only ~17% of dedicated P450c21"]},{"year":2010,"claim":"How estrogen suppresses CYP2C19 was unknown; an ERE half-site mediating ERα-dependent transcriptional repression was identified, establishing negative hormonal regulation distinct from direct enzyme inhibition.","evidence":"Luciferase reporter, EMSA, ChIP, mutagenesis, and RT-PCR in human hepatocytes","pmids":["20675569"],"confidence":"High","gaps":["Coregulator complexes mediating repression not identified","In vivo physiological estrogen effect not quantified"]},{"year":2013,"claim":"The molecular mechanism of the increased-function *17 allele was clarified; allelic mRNA quantification confirmed *17 acts in cis to elevate transcription and revealed additional regulatory variants.","evidence":"qRT-PCR, allelic mRNA expression ratio, and enzyme activity in human liver samples","pmids":["23412869"],"confidence":"Medium","gaps":["Specific transcription factor altered by *17 not pinpointed","Additional regulatory variants uncharacterized"]},{"year":2013,"claim":"Whether drug induction of CYP2C19 is genotype-dependent was tested; efavirenz increased omeprazole 5-hydroxylation differentially across CYP2C19 genotypes in a non-stereoselective manner.","evidence":"Controlled clinical PK study with genotype stratification and LC-MS/MS enantiomer measurement","pmids":["23629159"],"confidence":"Medium","gaps":["Receptor mediating efavirenz induction not directly identified","CYP2B6 contribution excluded only by genotype association"]},{"year":2014,"claim":"Post-transcriptional control of CYP2C19 was undefined; direct miRNA-transcript binding established hsa-miR-29a-3p as a suppressor of expression in cells and human liver.","evidence":"In silico analysis, RNA EMSA, and qRT-PCR in HepaRG cells and human liver tissue","pmids":["26296572"],"confidence":"Medium","gaps":["Binding within coding region rather than canonical 3'UTR not mechanistically dissected","In vivo loss-of-miRNA validation absent"]},{"year":2014,"claim":"Several findings extended substrate scope and variant impact, defining CYP2C19 bioactivation and stereoselective and loss-of-function behavior across drugs.","evidence":"Recombinant enzyme assays for clopidogrel/2-oxo-clopidogrel (*10), rhein bioactivation with GSH trapping and hepatocyte rescue, and NHP-ortholog SRS mutagenesis with docking","pmids":["24945780","25815638","25036290"],"confidence":"Medium","gaps":["Rhein hepatotoxicity demonstrated in rat hepatocytes, not human in vivo","NHP-ortholog substitutions may not map directly to human variants"]},{"year":2016,"claim":"Whether CYP2C19 has a role beyond drug metabolism was tested; humanized transgenic mice linked CYP2C19 expression to hippocampal BDNF and serotonin signaling, implicating it in neurodevelopment.","evidence":"2C19TG transgenic mouse behavioral and biochemical assays including BDNF, serotonin metabolites, and ERK1/2/GSK3β phosphorylation","pmids":["27895323"],"confidence":"Medium","gaps":["Endogenous neural substrate of CYP2C19 not identified","Transgene overexpression may not reflect physiological brain levels"]},{"year":2020,"claim":"The proteome-wide stability consequences of CYP2C19 variation were unknown; deep mutational scanning quantified abundance of thousands of variants and localized SRS4 as a CYP2C19-specific determinant of stability and substrate specificity versus CYP2C9.","evidence":"VAMP-seq deep mutational scanning of protein abundance in cultured human cells","pmids":["39319420","32004414"],"confidence":"High","gaps":["Abundance does not directly measure catalytic competence","Functional consequences for specific clinical substrates not assayed per variant"]},{"year":2024,"claim":"Variant effects on a newer therapeutic substrate were profiled; recombinant CYP2C19 variant systems showed bidirectional effects on tofacitinib metabolism and characterized inhibitor kinetics.","evidence":"Recombinant CYP2C19/CYP3A4 variant expression with UPLC-MS/MS metabolite quantification and inhibitor kinetics","pmids":["38719708"],"confidence":"Medium","gaps":["Clinical PK consequences not measured","Single-lab recombinant system"]},{"year":null,"claim":"Whether CYP2C19 functions as a physiologically significant arachidonic acid epoxygenase and how its endogenous (steroid and lipid) substrate activities integrate with its neurodevelopmental role remains unresolved.","evidence":"","pmids":[],"confidence":"Low","gaps":["EET production inferred only from serum DHET in PM patients without a direct enzyme assay (idx 21)","Endogenous brain substrate undefined","No structural model linking active-site geometry to endogenous lipid metabolism"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016491","term_label":"oxidoreductase activity","supporting_discovery_ids":[3,4,5,8,11,20]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[3,5,8,9,11]}],"localization":[{"term_id":"GO:0005783","term_label":"endoplasmic reticulum","supporting_discovery_ids":[3]}],"pathway":[],"complexes":[],"partners":["POR"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"P33261","full_name":"Cytochrome P450 2C19","aliases":["(R)-limonene 6-monooxygenase","(S)-limonene 6-monooxygenase","(S)-limonene 7-monooxygenase","CYPIIC17","CYPIIC19","Cytochrome P450-11A","Cytochrome P450-254C","Fenbendazole monooxygenase (4'-hydroxylating)","Mephenytoin 4-hydroxylase"],"length_aa":490,"mass_kda":55.9,"function":"A cytochrome P450 monooxygenase involved in the metabolism of polyunsaturated fatty acids (PUFA) (PubMed:18577768, PubMed:19965576, PubMed:20972997). Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate, and reducing the second into a water molecule, with two electrons provided by NADPH via cytochrome P450 reductase (NADPH--hemoprotein reductase) (PubMed:18577768, PubMed:19965576, PubMed:20972997). Catalyzes the hydroxylation of carbon-hydrogen bonds. Hydroxylates PUFA specifically at the omega-1 position (PubMed:18577768). Catalyzes the epoxidation of double bonds of PUFA (PubMed:19965576, PubMed:20972997). Also metabolizes plant monoterpenes such as limonene. Oxygenates (R)- and (S)-limonene to produce carveol and perillyl alcohol (PubMed:11950794). Responsible for the metabolism of a number of therapeutic agents such as the anticonvulsant drug S-mephenytoin, omeprazole, proguanil, certain barbiturates, diazepam, propranolol, citalopram and imipramine. 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psychiatry","url":"https://pubmed.ncbi.nlm.nih.gov/34497262","citation_count":12,"is_preprint":false},{"pmid":"34040417","id":"PMC_34040417","title":"Pharmacogenomics in the United States Community Pharmacy Setting: The Clopidogrel-CYP2C19 Example.","date":"2021","source":"Pharmacogenomics and personalized medicine","url":"https://pubmed.ncbi.nlm.nih.gov/34040417","citation_count":12,"is_preprint":false},{"pmid":"17614006","id":"PMC_17614006","title":"Relative roles of CYP2C19 and CYP3A4/5 in midazolam 1'-hydroxylation.","date":"2007","source":"Xenobiotica; the fate of foreign compounds in biological systems","url":"https://pubmed.ncbi.nlm.nih.gov/17614006","citation_count":12,"is_preprint":false},{"pmid":"11694260","id":"PMC_11694260","title":"CYP2C19 genotype determines enzyme activity and inducibility of S-mephenytoin hydroxylase.","date":"2001","source":"Clinica chimica acta; international journal of clinical chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/11694260","citation_count":11,"is_preprint":false},{"pmid":"26639454","id":"PMC_26639454","title":"CYP2C19 drug-drug and drug-gene interactions in ED patients.","date":"2015","source":"The American journal of emergency medicine","url":"https://pubmed.ncbi.nlm.nih.gov/26639454","citation_count":11,"is_preprint":false},{"pmid":"24315317","id":"PMC_24315317","title":"Investigation of CYP2C19 allele and genotype frequencies in Iranian population using experimental and computational approaches.","date":"2013","source":"Thrombosis research","url":"https://pubmed.ncbi.nlm.nih.gov/24315317","citation_count":11,"is_preprint":false},{"pmid":"31441095","id":"PMC_31441095","title":"Development and validation of T-ARMS-PCR to detect CYP2C19*17 allele.","date":"2019","source":"Journal of clinical laboratory analysis","url":"https://pubmed.ncbi.nlm.nih.gov/31441095","citation_count":11,"is_preprint":false},{"pmid":"39010708","id":"PMC_39010708","title":"Inflammation altered correlation between CYP2C19 genotype and CYP2C19 activity in patients receiving voriconazole.","date":"2024","source":"Clinical and translational science","url":"https://pubmed.ncbi.nlm.nih.gov/39010708","citation_count":10,"is_preprint":false},{"pmid":"36836519","id":"PMC_36836519","title":"Clinical Impact of the CYP2C19 Gene on Diazepam for the Management of Alcohol Withdrawal Syndrome.","date":"2023","source":"Journal of personalized medicine","url":"https://pubmed.ncbi.nlm.nih.gov/36836519","citation_count":10,"is_preprint":false},{"pmid":"24945780","id":"PMC_24945780","title":"The influence of the CYP2C19*10 allele on clopidogrel activation and CYP2C19*2 genotyping.","date":"2014","source":"Pharmacogenetics and genomics","url":"https://pubmed.ncbi.nlm.nih.gov/24945780","citation_count":10,"is_preprint":false},{"pmid":"30916611","id":"PMC_30916611","title":"Comparison between MassARRAY and pyrosequencing for CYP2C19 and ABCB1 gene variants of clopidogrel efficiency genotyping.","date":"2019","source":"Molecular membrane biology","url":"https://pubmed.ncbi.nlm.nih.gov/30916611","citation_count":10,"is_preprint":false},{"pmid":"31531091","id":"PMC_31531091","title":"Genetic Polymorphism of CYP2C19 in Pakistani Population.","date":"2019","source":"Iranian journal of pharmaceutical research : IJPR","url":"https://pubmed.ncbi.nlm.nih.gov/31531091","citation_count":10,"is_preprint":false},{"pmid":"36072540","id":"PMC_36072540","title":"Therapeutic drug monitoring and CYP2C19 genotyping guide the application of voriconazole in children.","date":"2022","source":"Translational pediatrics","url":"https://pubmed.ncbi.nlm.nih.gov/36072540","citation_count":10,"is_preprint":false},{"pmid":"38975048","id":"PMC_38975048","title":"The Diversity of CYP2C19 Polymorphisms in the Thai Population: Implications for Precision Medicine.","date":"2024","source":"The application of clinical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/38975048","citation_count":10,"is_preprint":false},{"pmid":"32493215","id":"PMC_32493215","title":"Bedside testing of CYP2C19 gene for treatment of patients with PCI with antiplatelet therapy.","date":"2020","source":"BMC cardiovascular disorders","url":"https://pubmed.ncbi.nlm.nih.gov/32493215","citation_count":10,"is_preprint":false},{"pmid":"36937863","id":"PMC_36937863","title":"From gene to dose: Long-read sequencing and *-allele tools to refine phenotype predictions of CYP2C19.","date":"2023","source":"Frontiers in pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/36937863","citation_count":9,"is_preprint":false},{"pmid":"25403437","id":"PMC_25403437","title":"CYP2C19 polymorphism increases the risk of endometriosis.","date":"2014","source":"Journal of assisted reproduction and genetics","url":"https://pubmed.ncbi.nlm.nih.gov/25403437","citation_count":9,"is_preprint":false},{"pmid":"25583161","id":"PMC_25583161","title":"Prevalence and significance of CYP2C19*2 and CYP2C19*17 alleles in a New Zealand acute coronary syndrome population.","date":"2015","source":"Internal medicine journal","url":"https://pubmed.ncbi.nlm.nih.gov/25583161","citation_count":9,"is_preprint":false},{"pmid":"38150171","id":"PMC_38150171","title":"PBPK modeling to predict the pharmacokinetics of pantoprazole in different CYP2C19 genotypes.","date":"2023","source":"Archives of pharmacal research","url":"https://pubmed.ncbi.nlm.nih.gov/38150171","citation_count":9,"is_preprint":false},{"pmid":"26899628","id":"PMC_26899628","title":"Stereoselective hydroxylation by CYP2C19 and oxidation by ADH4 in the in vitro metabolism of tivantinib.","date":"2016","source":"Xenobiotica; the fate of foreign compounds in biological systems","url":"https://pubmed.ncbi.nlm.nih.gov/26899628","citation_count":9,"is_preprint":false},{"pmid":"27288795","id":"PMC_27288795","title":"Association of MDR1, CYP2D6, and CYP2C19 gene polymorphisms with prophylactic migraine treatment response.","date":"2016","source":"Journal of the neurological sciences","url":"https://pubmed.ncbi.nlm.nih.gov/27288795","citation_count":9,"is_preprint":false},{"pmid":"30325490","id":"PMC_30325490","title":"Response to clopidogrel and of the cytochrome CYP2C19 gene polymorphism.","date":"2018","source":"La Tunisie medicale","url":"https://pubmed.ncbi.nlm.nih.gov/30325490","citation_count":8,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":56518,"output_tokens":6390,"usd":0.132702,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":15111,"output_tokens":4769,"usd":0.09739,"stage2_stop_reason":"end_turn"},"total_usd":0.230092,"stage1_batch_id":"msgbatch_01ACAxJQabDsht39JXeWG22d","stage2_batch_id":"msgbatch_01QEU22A9U5sbPTgsMzTmvSf","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2003,\n      \"finding\": \"The CYP2C19 promoter contains a constitutive androstane receptor/pregnane X receptor binding site (CAR-RE; -1891/-1876 bp) and a glucocorticoid-responsive element (GRE; -1750/-1736 bp). Gel-shift assays showed CAR-RE binds CAR and PXR; cotransfection with hCAR, mCAR, or hPXR in HepG2 cells upregulated CYP2C19 promoter transcription, and mutation of the -1891-bp CAR-RE abolished this upregulation. Dexamethasone activated CYP2C19 promoter constructs only when cotransfected glucocorticoid receptor (GR) was present, and mutation of the GRE abolished dexamethasone activation.\",\n      \"method\": \"Gel-shift (EMSA), cotransfection/reporter assays in HepG2 cells, site-directed mutagenesis, endogenous mRNA measurement\",\n      \"journal\": \"Molecular pharmacology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — multiple orthogonal methods (EMSA, reporter assay, mutagenesis, endogenous mRNA), single rigorous study with functional validation at each step\",\n      \"pmids\": [\"12869636\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Estrogen receptor α (ERα) downregulates CYP2C19 expression via a newly identified ERE half-site at position -151/-147 in the CYP2C19 promoter. EMSA and chromatin immunoprecipitation confirmed ERα binding to this element; mutations in the ERE half-site significantly inhibited ligand-dependent repression. Treatment of human hepatocytes with 17β-estradiol or 17α-ethinylestradiol significantly suppressed CYP2C19 transcription. Competitive inhibition of CYP2C19 enzymatic activity by these steroids required much higher concentrations than those needed for transcriptional inhibition, indicating the primary mechanism is transcriptional.\",\n      \"method\": \"Luciferase reporter assay, EMSA, chromatin immunoprecipitation (ChIP), site-directed mutagenesis, RT-PCR in human hepatocytes, enzymatic inhibition assays in stable HEK293-CYP2C19 cells\",\n      \"journal\": \"Molecular pharmacology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — multiple orthogonal methods (EMSA, ChIP, mutagenesis, reporter, human hepatocytes), single rigorous study\",\n      \"pmids\": [\"20675569\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"hsa-miR-29a-3p directly binds the CYP2C19 transcript coding region (predicted hybrid stability -23.3 kcal/mol) and suppresses CYP2C19 expression. RNA EMSA confirmed direct miRNA-mRNA binding; chemically induced upregulation of hsa-miR-29a-3p in HepaRG cells inversely correlated with CYP2C19 expression; inverse correlations between miR-29a-3p levels and CYP2C19 mRNA were also observed in human liver tissue samples.\",\n      \"method\": \"In silico analysis, RNA electrophoretic mobility shift assay (EMSA), qRT-PCR in HepaRG cells and human liver tissue\",\n      \"journal\": \"Biochemical pharmacology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — EMSA confirms direct binding, supported by two biological systems (cell line + human tissue), single lab\",\n      \"pmids\": [\"26296572\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"CYP2C19 (bacterially expressed, purified) can 21-hydroxylate progesterone with a Vmax/Km ~17% of that of the dedicated adrenal 21-hydroxylase P450c21, and a Km of ~11 µM. CYP2C19 cannot 21-hydroxylate 17-hydroxyprogesterone. The common P450 oxidoreductase (POR) variant A503V did not substantially alter these activities.\",\n      \"method\": \"Reconstituted in vitro enzyme assay with bacterially expressed N-terminally modified C-His-tagged CYP2C19 and wild-type or A503V POR; radiolabeled substrate, Km/Vmax measurement\",\n      \"journal\": \"The Journal of clinical endocrinology and metabolism\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — reconstituted in vitro assay with kinetic characterization and POR variant comparison, single lab but rigorous biochemical study\",\n      \"pmids\": [\"18957504\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"Active-site characterization of CYP2C19 using N-3 alkyl-substituted phenytoin, nirvanol, and barbiturate derivatives showed all are competitive inhibitors. Inhibitor stereochemistry is an important determinant of potency toward CYP2C19 (but not CYP2C9). (S)-(+)-N-3-benzylnirvanol and (R)-(-)-N-3-benzylphenobarbital are highly potent and selective CYP2C19 inhibitors (Ki < 250 nM). CYP2C19 preferentially orients N-3 substituents away from the active oxygen species (metabolizes at C-5 phenyl substituents). A validated CoMFA model for CYP2C19 active-site geometry was developed.\",\n      \"method\": \"Recombinant enzyme competitive inhibition assays (Ki determination), metabolite identification, CoMFA modeling\",\n      \"journal\": \"Archives of biochemistry and biophysics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro inhibition kinetics with multiple substrate series, metabolite identification, and computational modeling in single rigorous study\",\n      \"pmids\": [\"15288804\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"CYP2C19 activates rhein (rhubarb anthraquinone) to a reactive epoxide intermediate, as demonstrated by IC50 shift experiments (IC50 shift value 1.989). CYP2C19 is the primary metabolic enzyme for rhein. In primary rat hepatocytes, co-addition of a CYP2C19 inhibitor with rhein restored mitochondrial membrane potential and reduced AST levels, indicating CYP2C19-mediated bioactivation drives rhein hepatotoxicity.\",\n      \"method\": \"IC50 shift assay, GSH-trapping (reactive metabolite identification), primary rat hepatocyte cytotoxicity assay, mitochondrial membrane potential measurement, AST assay\",\n      \"journal\": \"Xenobiotica\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal in vitro methods (IC50 shift, GSH trapping, cell-based rescue), single lab\",\n      \"pmids\": [\"25815638\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"CYP2C19 variant *19 (Ser51Gly/Ile331Val) expressed in yeast showed a 3-fold higher Km for S-mephenytoin 4'-hydroxylation compared to wild-type (CYP2C19.1B), with Vmax/Km reduced to 29–47% of wild-type, indicating decreased substrate affinity. CYP2C19 variant *18 (Arg329His/Ile331Val) showed no significant change in Km, Vmax, or Vmax/Km.\",\n      \"method\": \"Heterologous expression in yeast, enzyme kinetics (Km, Vmax determination) for S-mephenytoin 4'-hydroxylation\",\n      \"journal\": \"Xenobiotica\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — reconstituted in vitro kinetics with site-specific variants, but single lab, single substrate\",\n      \"pmids\": [\"17455109\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"CYP2C19 (recombinant) can catalyze midazolam 1'-hydroxylation with a Michaelis-Menten kinetic profile, and this activity is inhibited by the selective CYP2C19 inhibitor (+)-N-3-benzylnirvanol and by S-mephenytoin. However, the contribution of CYP2C19 to midazolam 1'-hydroxylation in human liver microsomes is minor compared to CYP3A4/5, as addition of (+)-N-3-benzylnirvanol did not change intrinsic clearance in HLM preparations.\",\n      \"method\": \"Recombinant CYP2C19 enzyme assay, selective inhibitor studies, correlation analysis in human liver microsomes\",\n      \"journal\": \"Xenobiotica\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — recombinant enzyme kinetics plus HLM correlation, two orthogonal approaches, single lab\",\n      \"pmids\": [\"17614006\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"CYP2C19 catalyzes stereoselective hydroxylation of tivantinib: CYP2C19 forms M5 (one hydroxylated metabolite stereoisomer) but not M4 (its stereoisomer), whereas CYP3A4/5 catalyzes both. CYP2C19 and CYP3A4/5 are the primary isoforms for tivantinib elimination.\",\n      \"method\": \"In vitro metabolism using recombinant CYP isoforms and human liver microsomes; metabolite identification and quantification\",\n      \"journal\": \"Xenobiotica\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — recombinant enzyme assays with metabolite identification demonstrating stereoselectivity, single lab\",\n      \"pmids\": [\"26899628\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"The CYP2C19*10 variant protein (expressed recombinantly) shows significantly decreased catalytic activity in the biotransformation of clopidogrel and its intermediate 2-oxo-clopidogrel compared to wild-type CYP2C19.1B, establishing *10 as a partial loss-of-function allele for clopidogrel bioactivation.\",\n      \"method\": \"Recombinant protein expression, enzymatic activity assay for clopidogrel and 2-oxo-clopidogrel metabolism\",\n      \"journal\": \"Pharmacogenetics and genomics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — direct enzymatic assay with recombinant protein, single lab, single substrate pair\",\n      \"pmids\": [\"24945780\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"CYP2C19 variants (cynomolgus macaque CYP2C19 with p.Phe100Asn, p.Ala103Val, p.Ile112Leu substitutions in substrate recognition sites) showed substantially reduced catalytic activity for flurbiprofen 4'-hydroxylation, omeprazole 5-hydroxylation, and R-/S-warfarin 7-hydroxylation compared to wild-type. Kinetic analysis of Ala103Val showed it diminishes homotropic cooperativity of CYP2C19 with R-warfarin, yielding low metabolic capacity.\",\n      \"method\": \"Site-directed mutagenesis, recombinant protein expression, metabolic assays, kinetic analysis, docking simulation\",\n      \"journal\": \"Biochemical pharmacology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — mutagenesis plus in vitro kinetics plus molecular docking, single lab, NHP ortholog\",\n      \"pmids\": [\"25036290\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"Omeprazole 5-hydroxylation in Chinese liver microsomes is mediated primarily by CYP2C19 (inhibited by anti-CYP2C8/9/19 antibody; activity correlates with S-mephenytoin 4'-hydroxylation and CYP2C19 protein content), while omeprazole sulfoxidation is mediated primarily by CYP3A4 (anti-CYP3A4 antibody abolished >87% of this activity; correlated with CYP3A4 content).\",\n      \"method\": \"HPLC metabolite quantification, monoclonal antibody inhibition, Western blot, correlation analysis in human liver microsomes\",\n      \"journal\": \"Acta pharmacologica Sinica\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — antibody inhibition, immunoquantification, and correlation analysis in HLMs, single lab, multiple orthogonal approaches\",\n      \"pmids\": [\"11501187\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"CYP2C19 protein and catalytic activity (S-mephenytoin 4'-hydroxylation) are detectable at 12–15% of mature values as early as 8 weeks of gestation, remain similar throughout prenatal development, do not change at birth, increase linearly over the first 5 postnatal months, and reach adult levels by 10 years of age. This ontogenic pattern differs from CYP2C9, suggesting different developmental regulatory mechanisms.\",\n      \"method\": \"Western blotting and probe substrate activity assays (mephenytoin 4'-hydroxylation) in 237 liver microsomal samples spanning 8 weeks gestation to 18 years\",\n      \"journal\": \"The Journal of pharmacology and experimental therapeutics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct protein and activity quantification across large developmental sample set, single lab, two orthogonal readouts\",\n      \"pmids\": [\"14634042\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"The CYP2C19*17 allele is associated with increased hepatic CYP2C19 mRNA expression (~1.8-fold in heterozygotes, ~2.9-fold in homozygotes) and increased allelic mRNA expression ratio (~1.8-fold), confirming *17 as a cis-regulatory polymorphism enhancing CYP2C19 transcription. Additional regulatory variants beyond *17 also contribute to CYP2C19 expression variability in African American samples.\",\n      \"method\": \"qRT-PCR for mRNA quantification, allelic mRNA expression ratio (SNaPshot), enzyme activity assay (S-mephenytoin as substrate), sequencing of promoter region in human liver samples\",\n      \"journal\": \"Drug metabolism and drug interactions\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — qRT-PCR, allelic expression, and enzyme activity in human liver tissue, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"23412869\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Dicloxacillin induces CYP2C19 (as well as CYP2C9 and CYP3A4) in vivo (significant reduction in omeprazole AUC; geometric mean ratio 0.33) and in vitro in primary human hepatocytes (dose-dependent increase in CYP expression and activity). This induction is mechanistically mediated through activation of the pregnane X receptor (PXR), as demonstrated by luciferase reporter assays.\",\n      \"method\": \"Randomized crossover pharmacokinetic clinical trial, primary human hepatocyte gene expression and activity assays, PXR luciferase reporter assay\",\n      \"journal\": \"British journal of clinical pharmacology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — in vivo PK study plus mechanistic in vitro hepatocyte plus PXR reporter assay, multiple orthogonal methods\",\n      \"pmids\": [\"29105855\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Deep mutational scanning of CYP2C19 in cultured human cells (landing-pad system) measuring steady-state protein abundance for 7,660 single amino acid variants identified 36 of 121 missense variants that reduce CYP2C19 protein to <25% of wild-type. Variants at substrate recognition site 4 (SRS4) specifically reduced abundance in CYP2C19 but not CYP2C9, and joint analysis revealed double/triple mutant interactions in this region. These positions contribute to differing thermodynamic properties and substrate specificity between the two homologs.\",\n      \"method\": \"Deep mutational scanning (variant abundance by massively parallel sequencing, VAMP-seq) in cultured human cells\",\n      \"journal\": \"Genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — high-throughput functional assay measuring protein abundance of thousands of variants in human cells, confirmed critical structural features, rigorous single study\",\n      \"pmids\": [\"39319420\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"CYP2C19 missense variant scanning (DMS landing-pad system) identified 36 of 121 CYP2C19 ORF missense variants with <25% of wild-type protein expression, demonstrating that a significant fraction of genomic missense variants cause loss of CYP2C19 protein.\",\n      \"method\": \"Deep mutational scanning in human cells, protein expression quantification\",\n      \"journal\": \"Clinical and translational science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — high-throughput functional genomics, single lab, protein expression as functional readout\",\n      \"pmids\": [\"32004414\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"CYP2C19 is expressed in adult human liver and in the fetal brain during neurodevelopment. Transgenic mice carrying the human CYP2C19 gene (2C19TG) showed impaired hippocampal BDNF homeostasis under stress, increased serotonin turnover reduction in hippocampus, and increased ERK1/2 and GSK3β phosphorylation, suggesting CYP2C19 modulates brain serotonin and BDNF signaling beyond classical drug metabolism.\",\n      \"method\": \"Transgenic mouse model (2C19TG), forced swim test, hippocampal BDNF and serotonin metabolite measurements, Western blot for ERK1/2 and GSK3β phosphorylation\",\n      \"journal\": \"Molecular psychiatry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple in vivo endpoints in transgenic model, single lab, several orthogonal biochemical readouts\",\n      \"pmids\": [\"27895323\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Efavirenz increases CYP2C19-mediated omeprazole metabolism (5-hydroxylation) in a CYP2C19 genotype-dependent manner: the magnitude of induction differed between CYP2C19 genotypes, and metabolic ratios of 5-hydroxylation were reduced in extensive and intermediate CYP2C19 metabolizers after efavirenz treatment, in a non-stereoselective manner. No significant association was found between CYP2B6 genotypes and this induction.\",\n      \"method\": \"Controlled pharmacokinetic clinical study in healthy subjects (n=57), CYP2C19/CYP2B6 genotyping, LC-MS/MS measurement of omeprazole enantiomers and metabolites\",\n      \"journal\": \"The pharmacogenomics journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — controlled clinical PK study with genotype stratification and stereospecific metabolite measurement, single lab\",\n      \"pmids\": [\"23629159\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"CYP2C19 and CYP3A4 variants differentially affect tofacitinib metabolism: 11 CYP2C19 variants showed increased M9 (main metabolite) production and 10 showed decreased production vs. CYP2C19.1, using recombinant human enzyme systems. Myricetin inhibits tofacitinib metabolism in a non-competitive manner in rat and human liver microsomes, but competitively in CYP3A4.18 and by a mixed mechanism in CYP3A4.1 and CYP3A4.28.\",\n      \"method\": \"Recombinant human CYP2C19 and CYP3A4 variant expression system, UPLC-MS/MS metabolite quantification, enzyme kinetics in RLM and HLM\",\n      \"journal\": \"Biomedicine & pharmacotherapy\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — recombinant enzyme system with multiple variants and inhibitor kinetics, single lab\",\n      \"pmids\": [\"38719708\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"CYP2C19 mediates stereoselective 4'-hydroxylation of R-mephobarbital: the mean plasma AUC of R-MPB was 92-fold greater in CYP2C19 poor metabolizers than in homozygous extensive metabolizers, and cumulative urinary 4'-hydroxy-MPB was 21-fold less in PMs. S-mephobarbital conversion to phenobarbital was not significantly affected by CYP2C19 genotype. A minor fraction of phenobarbital formation from MPB was associated with CYP2B6*6 allele.\",\n      \"method\": \"Controlled pharmacokinetic study in CYP2C19-genotyped subjects; plasma and urine drug/metabolite measurement; CYP2B6 genotyping\",\n      \"journal\": \"Pharmacogenetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — controlled human PK study with genotype stratification, single lab, clear genotype-phenotype relationship\",\n      \"pmids\": [\"15284537\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"CYP2C19 poor metabolizers (with two loss-of-function alleles *2/*3) have significantly lower serum dihydroxyeicosatrienoic acid (DHET, a surrogate for epoxyeicosatrienoic acids/EETs) levels compared to non-PMs in patients with microvascular angina, suggesting CYP2C19 has epoxygenase activity toward arachidonic acid producing EETs in vivo.\",\n      \"method\": \"CYP2C19 genotyping, serum DHET measurement (EET metabolite proxy) in microvascular angina patients and controls\",\n      \"journal\": \"International journal of cardiology. Heart & vasculature\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — indirect in vivo metabolite measurement, no direct enzyme assay for EET production, single observational study\",\n      \"pmids\": [\"28616567\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"CYP2C19 is a hepatic (and fetal brain-expressed) cytochrome P450 enzyme whose transcription is activated by CAR/PXR via a promoter CAR-RE element and by glucocorticoid receptor via a GRE, downregulated by ERα via a promoter ERE half-site, and post-transcriptionally suppressed by hsa-miR-29a-3p; the *17 allele acts as a cis-regulatory variant that increases mRNA ~2-fold, while *2 and other loss-of-function alleles reduce or abolish the enzyme; the enzyme stereoselectively hydroxylates substrates including S-mephenytoin, omeprazole, clopidogrel (to active metabolite), mephobarbital, tivantinib, and progesterone (21-hydroxylation), with active-site geometry that is sensitive to inhibitor stereochemistry and is distinct from the closely related CYP2C9.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"CYP2C19 is a hepatic cytochrome P450 monooxygenase that performs stereoselective oxidative metabolism of a broad range of clinical drugs and endogenous substrates [#4, #8]. Its transcription is governed by a network of nuclear receptors acting at defined promoter elements: CAR and PXR bind a CAR-RE (-1891/-1876) and the glucocorticoid receptor binds a GRE (-1750/-1736) to upregulate expression, while ERα binds an ERE half-site (-151/-147) to mediate ligand-dependent repression [#0, #1]; PXR activation also underlies xenobiotic induction by agents such as dicloxacillin [#14]. Expression is further constrained post-transcriptionally by direct binding of hsa-miR-29a-3p to the transcript coding region [#2], and the cis-regulatory *17 allele increases hepatic mRNA roughly two- to threefold [#13]. Catalytically, CYP2C19 hydroxylates S-mephenytoin, omeprazole (5-hydroxylation), R-mephobarbital, tivantinib, and clopidogrel, and bioactivates compounds including rhein to a hepatotoxic reactive epoxide [#11, #20, #8, #9, #5]; it also possesses minor capacity for progesterone 21-hydroxylation [#3]. Active-site geometry is sensitive to inhibitor stereochemistry and is distinguished from the closely related CYP2C9 by substrate recognition site residues, particularly SRS4, that determine both protein stability and substrate specificity [#4, #15]. Loss-of-function and altered-function missense variants, including *10, *18, *19, reduce catalytic activity or protein abundance, while a substantial fraction of genomic missense variants destabilize the protein [#6, #9, #15, #16]. Beyond drug metabolism, CYP2C19 is expressed in fetal brain and, in a humanized transgenic model, modulates hippocampal BDNF and serotonin signaling [#17].\",\n  \"teleology\": [\n    {\n      \"year\": 2000,\n      \"claim\": \"Establishing which P450 isoform drives a clinically important metabolic reaction was needed to assign drug-handling responsibility; this defined CYP2C19 as the principal omeprazole 5-hydroxylase distinct from CYP3A4-mediated sulfoxidation.\",\n      \"evidence\": \"Antibody inhibition, immunoquantification, and correlation analysis in human liver microsomes\",\n      \"pmids\": [\"11501187\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Does not resolve atomic active-site determinants of regioselectivity\", \"Population-specific to Chinese liver samples\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"How CYP2C19 transcription is controlled was unknown; identification of a CAR/PXR-binding CAR-RE and a GR-responsive GRE in the promoter established receptor-mediated transcriptional induction.\",\n      \"evidence\": \"EMSA, reporter assays, and site-directed mutagenesis in HepG2 cells with endogenous mRNA measurement\",\n      \"pmids\": [\"12869636\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Does not quantify relative contribution of each receptor in vivo\", \"Endogenous chromatin occupancy not tested by ChIP\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Whether CYP2C19 is developmentally regulated like its paralog was open; ontogeny profiling showed a distinct expression trajectory from fetal life to adulthood, implying separate developmental control from CYP2C9.\",\n      \"evidence\": \"Western blotting and mephenytoin 4'-hydroxylation activity across 237 liver microsomal samples\",\n      \"pmids\": [\"14634042\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Regulatory factors driving the developmental pattern not identified\", \"Brain ontogeny not assessed\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"The structural basis of CYP2C19 substrate/inhibitor selectivity was undefined; inhibitor stereochemistry studies and CoMFA modeling defined an active-site geometry that orients N-3 substituents and distinguishes CYP2C19 from CYP2C9.\",\n      \"evidence\": \"Recombinant enzyme competitive inhibition kinetics, metabolite identification, and CoMFA modeling\",\n      \"pmids\": [\"15288804\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No experimental crystal structure presented\", \"Model derived from limited inhibitor chemotypes\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Assigning the in vivo stereoselective metabolism of mephobarbital clarified CYP2C19's enantiomer-specific role; PM genotypes showed dramatically elevated R-mephobarbital exposure while S-conversion was genotype-independent.\",\n      \"evidence\": \"Controlled human PK study with CYP2C19 genotyping and plasma/urine metabolite measurement\",\n      \"pmids\": [\"15284537\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanistic basis of enantiomer discrimination not structurally resolved\", \"Limited to one substrate\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Defining the functional consequences of natural variants was needed for pharmacogenetic interpretation; kinetic characterization showed *19 reduces substrate affinity for S-mephenytoin while *18 is functionally neutral.\",\n      \"evidence\": \"Heterologous yeast expression and Km/Vmax kinetics for S-mephenytoin 4'-hydroxylation\",\n      \"pmids\": [\"17455109\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single substrate tested\", \"Yeast expression may not reflect human hepatic context\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Whether CYP2C19 contributes meaningfully to midazolam metabolism was tested; recombinant enzyme catalyzed 1'-hydroxylation but inhibitor studies showed its hepatic contribution is minor relative to CYP3A4/5.\",\n      \"evidence\": \"Recombinant enzyme kinetics with selective inhibitor and HLM correlation analysis\",\n      \"pmids\": [\"17614006\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Does not address physiological relevance in special populations\", \"Single-lab HLM correlation\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Whether CYP2C19 acts on endogenous steroids was unresolved; reconstituted assays showed it can 21-hydroxylate progesterone but not 17-hydroxyprogesterone, defining a restricted endogenous substrate capacity.\",\n      \"evidence\": \"Reconstituted in vitro assay with purified CYP2C19 and POR, radiolabeled substrate kinetics\",\n      \"pmids\": [\"18957504\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological significance of progesterone 21-hydroxylation in vivo unknown\", \"Activity is only ~17% of dedicated P450c21\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"How estrogen suppresses CYP2C19 was unknown; an ERE half-site mediating ERα-dependent transcriptional repression was identified, establishing negative hormonal regulation distinct from direct enzyme inhibition.\",\n      \"evidence\": \"Luciferase reporter, EMSA, ChIP, mutagenesis, and RT-PCR in human hepatocytes\",\n      \"pmids\": [\"20675569\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Coregulator complexes mediating repression not identified\", \"In vivo physiological estrogen effect not quantified\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"The molecular mechanism of the increased-function *17 allele was clarified; allelic mRNA quantification confirmed *17 acts in cis to elevate transcription and revealed additional regulatory variants.\",\n      \"evidence\": \"qRT-PCR, allelic mRNA expression ratio, and enzyme activity in human liver samples\",\n      \"pmids\": [\"23412869\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Specific transcription factor altered by *17 not pinpointed\", \"Additional regulatory variants uncharacterized\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Whether drug induction of CYP2C19 is genotype-dependent was tested; efavirenz increased omeprazole 5-hydroxylation differentially across CYP2C19 genotypes in a non-stereoselective manner.\",\n      \"evidence\": \"Controlled clinical PK study with genotype stratification and LC-MS/MS enantiomer measurement\",\n      \"pmids\": [\"23629159\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Receptor mediating efavirenz induction not directly identified\", \"CYP2B6 contribution excluded only by genotype association\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Post-transcriptional control of CYP2C19 was undefined; direct miRNA-transcript binding established hsa-miR-29a-3p as a suppressor of expression in cells and human liver.\",\n      \"evidence\": \"In silico analysis, RNA EMSA, and qRT-PCR in HepaRG cells and human liver tissue\",\n      \"pmids\": [\"26296572\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Binding within coding region rather than canonical 3'UTR not mechanistically dissected\", \"In vivo loss-of-miRNA validation absent\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Several findings extended substrate scope and variant impact, defining CYP2C19 bioactivation and stereoselective and loss-of-function behavior across drugs.\",\n      \"evidence\": \"Recombinant enzyme assays for clopidogrel/2-oxo-clopidogrel (*10), rhein bioactivation with GSH trapping and hepatocyte rescue, and NHP-ortholog SRS mutagenesis with docking\",\n      \"pmids\": [\"24945780\", \"25815638\", \"25036290\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Rhein hepatotoxicity demonstrated in rat hepatocytes, not human in vivo\", \"NHP-ortholog substitutions may not map directly to human variants\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Whether CYP2C19 has a role beyond drug metabolism was tested; humanized transgenic mice linked CYP2C19 expression to hippocampal BDNF and serotonin signaling, implicating it in neurodevelopment.\",\n      \"evidence\": \"2C19TG transgenic mouse behavioral and biochemical assays including BDNF, serotonin metabolites, and ERK1/2/GSK3β phosphorylation\",\n      \"pmids\": [\"27895323\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Endogenous neural substrate of CYP2C19 not identified\", \"Transgene overexpression may not reflect physiological brain levels\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"The proteome-wide stability consequences of CYP2C19 variation were unknown; deep mutational scanning quantified abundance of thousands of variants and localized SRS4 as a CYP2C19-specific determinant of stability and substrate specificity versus CYP2C9.\",\n      \"evidence\": \"VAMP-seq deep mutational scanning of protein abundance in cultured human cells\",\n      \"pmids\": [\"39319420\", \"32004414\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Abundance does not directly measure catalytic competence\", \"Functional consequences for specific clinical substrates not assayed per variant\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Variant effects on a newer therapeutic substrate were profiled; recombinant CYP2C19 variant systems showed bidirectional effects on tofacitinib metabolism and characterized inhibitor kinetics.\",\n      \"evidence\": \"Recombinant CYP2C19/CYP3A4 variant expression with UPLC-MS/MS metabolite quantification and inhibitor kinetics\",\n      \"pmids\": [\"38719708\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Clinical PK consequences not measured\", \"Single-lab recombinant system\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"Whether CYP2C19 functions as a physiologically significant arachidonic acid epoxygenase and how its endogenous (steroid and lipid) substrate activities integrate with its neurodevelopmental role remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"EET production inferred only from serum DHET in PM patients without a direct enzyme assay (idx 21)\", \"Endogenous brain substrate undefined\", \"No structural model linking active-site geometry to endogenous lipid metabolism\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016491\", \"supporting_discovery_ids\": [3, 4, 5, 8, 11, 20]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [3, 5, 8, 9, 11]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005783\", \"supporting_discovery_ids\": [3]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:1430728\", \"supporting_discovery_ids\": []}\n    ],\n    \"complexes\": [],\n    \"partners\": [\n      \"POR\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}