{{Rsnum
|rsid = 57081121
|Gene = CYP2C19
|Orientation=plus
|ReferenceAllele=G
|geno1=(A;A)
|geno2=(A;G)
|geno3=(G;G)
|Chromosome=10
|position=94780653
|Assembly=GRCh38
|GenomeBuild=38.1
|dbSNPBuild=141
|Status=Merged
|Merged=4986893
|Gene_s=CYP2C19
}}[[rs57081121]](A) is an allele defining the CYP2C19*3 form of this cytochrome p450.{{PMID|18521743}}

As a nonfunctioning [[CYP2C19]], this variant would be expected to be a poor metabolizer of several commonly prescribed drugs, including anti-[[ulcer]] drugs like [[omeprazole]] (trade names [[Losec]] and [[Prilosec]]), [[esomeprazole]] (trade name [[Nexium]]), and [[lansoprazole]] ([[Prevacid]]).