{{Rsnum
|rsid=56337013
|geno1 = (C;C)
|geno2 = (C;T)
|geno3 = (T;T)
|Orientation=plus
|ReferenceAllele=C
|MissenseAllele=T
|Chromosome=10
|position=94852738
|Gene=CYP2C19
|Assembly=GRCh38
|GenomeBuild=38.1
|dbSNPBuild=141
|Summary=Clopidogrel (Plavix®)
|Gene_s=CYP2C19
}}{{CPMC SNP
|link=https://cpmc.coriell.org/Sections/Results/Plavix.aspx?PgId=212
}}
The [[rs56337013]](T) allele defines the [[CYP2C19]] variant known as CYP2C19*5.

This variant is quite rare (< 1% of Caucasians or Chinese), and leads to a poor metabolizer phenotype.
{{PMID|10022751}}

{{PharmGKB
|RSID=rs56337013
|Name_s=CYP2C19:1297C>T; R433W
|Gene_s=CYP2C19
|Feature=Exon
|Evidence=PubMed ID:10022751
|Annotation=This variant is the defining SNP for CYP2C19*5 and contributes to the S-mephenytoin poor metabolizer phenotype in caucasians and chinese. The Arg433 to Trp mutation in the heme-binding region essentially abolishes CYP2C19 activity toward S-mephenytoin and tolbutamide.
|Drugs=mephenytoin; tolbutamide
|Drug Classes=
|Diseases=
|Curation Level=Curated
|PharmGKB Accession ID=PA162356002
}}
{{PMID Auto
|PMID=21247447
|Title=CYP2C19 and ABCB1 gene polymorphisms are differently distributed according to ethnicity in the Brazilian general population
|OA=1
}}
{{omim
|id=124020
|rsnum=56337013
|variant=0002
}}{{ClinVar
|rsid=56337013
|Reversed=0
|FwdREF=C
|FwdALT=T
|REF=C
|ALT=T
|RSPOS=96612495
|CHROM=10
|dbSNPBuildID=129
|SSR=0
|SAO=1
|VP=0x050268000000000402110100
|GENEINFO=CYP2C19:1557
|GENE_NAME=CYP2C19
|GENE_ID=1557
|WGT=0
|VC=SNV
|CLNALLE=1
|CLNHGVS=NC_000010.10:g.96612495C>T
|CLNORIGIN=1
|CLNSIG=5
|Tags=PM;PMC;S3D;HD;OTHERKG;LSD;OM
|CLNACC=RCV000018396.26
|CLNDBN=Mephenytoin, poor metabolism of
|CLNDSDB=MedGen
|CLNDSDBID=C1836024
|CLNSRC=OMIM Allelic Variant
|CLNSRCID=124020.0002
|Disease=Mephenytoin
}}