CYP2D6

About CYP2D6

CYP2D6 on chromosome 22q13.2 encodes a cytochrome P450 enzyme in the liver that metabolizes a large share of commonly used medicines, including many antidepressants, antipsychotics, beta blockers, and opioids, some of which, like codeine and tamoxifen, are converted by it into more active forms. CYP2D6 is highly polymorphic, with many alleles including non functional variants, reduced function variants, and whole gene deletions and duplications. As a result, people are commonly grouped as poor, intermediate, normal, or ultrarapid metabolizers, and the frequency of these groups varies considerably between populations. It is one of the most important genes in pharmacogenomics, and organizations such as the Clinical Pharmacogenetics Implementation Consortium publish guidance on interpreting CYP2D6 results for specific drugs. Its genotyping is technically challenging because of a nearby highly similar pseudogene, CYP2D7.