The enzyme CYP2D6 (full name: Cytochrome P450 2D6) is involved in the metabolisation of xenobiotics, such as drugs. Around 20 to 25% of all drugs are metabolised by CYP2D6.
Drugs metabolized by the enzyme CYP2D6 include:
- Beta blockers such as timolol, metoprolol, propranolol, carvedilol
- Antidepressants such as amitriptyline, clomipramine, duloxetine, fluoxetine, imipramine, paroxetine, nortriptyline, venlafaxine
- Antipsychotics such as haloperidol, risperidone, zuclopenthixol, pimozide, aripiprazole
- Opioids such as codeine, tramadol, oxycodone
- Antiarrhythmic drugs such as flecainide, propafenone
- Other drugs such as atomoxetine (for ADHD), tamoxifen (inhibits growth of oestrogen-sensitive tumours)
The activity of the enzyme CYP2D6 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 CYP2D6 gene.
When a genotype is determined these variations in the CYP2D6 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 CYP2D6 genotype is CYP2D6*1/*4.
At iGene we determine the following variants (alleles) of the CYP2D6 gene: CYP2D6*3, CYP2D6*4, CYP2D6*6, CYP2D6*7, CYP2D6*8, CYP2D6*10, CYP2D6*11, CYP2D6*12, CYP2D6*14, CYP2D6*17, CYP2D6*20, CYP2D6*29, CYP2D6*33, CYP2D6*35, CYP2D6*38, CYP2D6*41, CYP2D6*42 and other (classified as CYP2D6*1).
Gene deletion (*5) and duplication are not currently determined.