CYP2D6 Genotyping

The CYP2D6 gene codes for the CYP2D6 enzyme, which catalyses the metabolism of a large number of clinically important drugs including antidepressants, neuroleptics, some antiarrhythmics, lipophilic β-adrenoceptor blockers and opioids. Polymorphisms in this gene (genetic variants) hence affect pharmacokinetics of about 50% of the drugs in clinical use, which are CYP2D6 substrates. Predictive CYP2D6 genotyping is thusestimated to be beneficial for treatment of about 30–40% of CYP2D6 drug substrates, that is, for about 7–10% of all drugs clinically used.