The DRD2 TaqIA A1/A2 version causes less dopamine receptors. Doesn't learn from mistakes well. Reduced response to errors and increased addictive behavior [PMID 18063800] Men may have half the risk of Obsessive Compulsive Disorder but higher risk of ADHD. Women have lower Persistence. 0.87x reduced risk of Tardive Diskinesia when taking dopamine receptor antagonists. Slightly increased risk of alcoholism and smoking addiction. Slower recovery from traumatic brain injury. Lower risk of postoperative nausea within 6 hours of surgery. Bupropion (Wellbutrin, Budeprion, Prexaton, Elontril, Aplenzin, Zyban, Voxra) doesn't help to quit smoking[PMID 18058343]. Increased obesity due to decreased pleasure response to food.
DRD2/ANKK1 TaqIA polymorphism is not associated with early infant temperament. There were no differences in the temperament style distribution between the T-carrier and non-T carrier groups. There were also no statistically significant differences between the two groups in the score of the nine temperament dimensions. [PMID 20199723]
Extrapyramidal adverse effects are associated with increased drug occupancy of the dopamine 2 receptors DRD2. The A1 allele of the DRD2/ANKK1, rs1800497, is associated with decreased striatal DRD2 density. Results strongly suggested that A1+ variants of the DRD2/ANKK1 Taq1A allele do confer an associated risk for akathisia in patients who were treated with second-generation antipsychotics SGAs, and these variants may explain inconsistencies found across prior studies, when comparing FGAs and SGAs. [PMID 23118020]
[PMID 23118020] DRD2/ANKK1 Taq1A (rs 1800497 C>T) genotypes are associated with susceptibility to second generation antipsychotic-induced akathisia.
[PMID 23840506] Multivariate analysis of dopaminergic gene variants as risk factors of heroin dependence.
[PMID 20199723] [DRD2/ANKK1 Taq IA polymorphism and early infant temperament].