NCIt definition : Human CYP2D6*12 allele is located in the vicinity of 22q13.1 and is approximately
4 kb in length. This allele, a variant form of the CYP2D6 wild-type allele, encodes
cytochrome P450 2D6*12 protein. The CYP2D6*12 allele exhibits a clinically-relevant
SNP (g.124G A) in exon 1 that results in a G42R coding change. This alteration in
protein sequence abolishes the enzymatic activity of the cytochrome P450 2D6*12 protein.;