CYP2C8 polymorphism among the Portuguese.

Cytochrome P450 2C8 (CYP2C8) is a polymorphic phase I drug-metabolising enzyme involved in the metabolism of a wide variety of xenobiotics, as well as a proposed player in the regulation of vascular tone. Polymorphisms in this gene may have an impact on the metabolism of therapeutic drugs such as paclitaxel and verapamil. In this report we have determined the frequencies of the main non-synonymous CYP2C8 alleles, 805A>T (CYP2C8*2), 416G>A/1196A>G (CYP2C8*3) and 792C>G (CYP2C8*4) in a sample representative of Portuguese Caucasians. The allelic frequencies determined were 1.2%, 19.8%, and 6.4% for CYP2C8*2, CYP2C8*3, and CYP2C*4, respectively. The observed CYP2C8*3 prevalence is significantly different from the frequencies previously reported in North European populations.