The enzyme CYP2C9 (full name: Cytochrome P450 2C9) is involved in the metabolisation of xenobiotics, such as drugs. Around 10 to 20% of all drugs are metabolised by CYP2C9.
Drugs that can be metabolised by the enzyme CYP2C9 include:
- NSAIDs such as naproxen, diclofenac and ibuprofen
- Antihyperglycemic drugs such as tolbutamide, glipizide, glimepiride and nateglinide
- Antihypertensives such as losartan and irbesartan
- Anticoagulants such as S-warfarin, acenocoumarol and phenprocoumon
- Other drugs such as phenytoin (anticonvulsant), fluvastatin (cholesterol-lowering drug) and tamoxifen (anti-oestrogen)
Genetic predisposition
The activity of the enzyme CYP2C9 varies from one individual to another.
As a result, the efficacy of a drug can differ from person to person, as can the potential side effects. This variation can be partly explained by genetic variations in the CYP2C9 gene.
When a genotype is determined these variations in the CYP2C9 gene are indicated by two so-called alleles.
Each allele has a name consisting of an asterisk (*) and a number.
An example of a possible CYP2C9 genotype is CYP2C9*2/*3.
At iGene we determine the following variants (alleles) of the CYP2C9 gene:
CYP2C9*2, CYP2C9*3, CYP2C9*4, CYP2C9*5, CYP2C9*6, CYP2C9*8, CYP2C9*11, CYP2C9*13, CYP2C9*15, CYP2C9*25 and other (classified as CYP2C9*1).