How do other CYP450 genes contribute to drug metabolism?
Not all enzymes and not all polymorphisms are meaningful when it comes to their impact on drug metabolism. This table adapted from Ingelman-Sundberg 2004 demonstrates specific polymorphisms that have an impact on the pharmacokinetics of drugs metabolized by the enzyme in question. The most important polymorphisms are found with the CYP2D6, CYP2C9, and CYP2C19 genes. While CYP3A4 is very important to drug metabolism, it rarely mutates. Also, it remains questionable how much of the interindividual variability in CYP1A2 activity is explained by polymorphism. CYP2D6 is of particular importance because it frequently mutates into more than 70 known allelic variations. Both CYP2C9 and CYP2C19, which represent a significant part of drug metabolism, are also known to mutate. The AmpliChip CYP450 Test looks only at polymorphisms that have been shown to have an impact on drug metabolism for CYP2D6 and for CYP2C9. The AmpliChip CYP450 Test covers all the major polymorphisms listed for CYP2D6 and C
