- T (minor) allele results in non-functional CYP2D6*4 protein.
- C (major) allele results in normal levels of CYP2D6*4 protein
The Minor "T" allele is associated with:
- 3-8X Parkinson's risk upon exposure to pesticides based on dose (R,R2).
- Lower benefits of the drug Tomoxifen, whose active form is formed via CYP2D6 metabolism.
- More side effects to TCA drugs because of slow metabolizing.
- ~4x increased risk Bradycardia from beta blockers (R).
- 6 fold more side effects upon switching antidepressants (TT) (R).
- Lower maintenance doses of antidepressants (TT) (R).
- Lower risk of bladder and lung cancer (R).
- Less severe neurodegeneration in Alzheimer's (R).
- Poor metabolism of debrisoquine (TT) (R).
Some drugs are typically first metabolized by CYP2D6 include:
- many antidepressants