title: 1846G>A polymorphism of CYP2D6 gene and extrapyramidal side effects during antipsychotic therapy among Russians and Tatars: a pilot study.
abstract: Сytochrome P450 CYP2D6 activity affects antipsychotic therapy safety. 1846G>A (CYP2D6*4) polymorphism frequency varies among different ethnic groups.
  
  
  
  We studied 1846G>A polymorphism in Tatar and Russian schizophrenic patients taking different antipsychotics and association of 1846G>A polymorphism and extrapyramidal disorders (EPD) frequency in schizophrenic patients on haloperidol monotherapy in daily doses up to 20 mg.
  
  
  
  Heterozygous 1846GA genotype frequency among Tatars was lower (23.8% vs. 32.4% in Russians), but the differences did not reach statistical significance. The 1846A allele frequency among Tatars was also lower (11.9% vs. 24.3% in Russians), but the difference was not quite significant (p=0.0592). Average daily haloperidol dose in the group without EPD was significantly higher than in the group with EPD (11.35±4.6 vs. 13.87±3.3 mg, p=0.0252), but average daily haloperidol dose/weight ratios in the compared groups had no significant differences. A statistically significant association between EPD development and heterozygous 1846GA genotype and 1846A allele carrier frequency was revealed among all schizophrenic patients and among those of Tatars.
  
  
  
  Further well-designed pharmacogenetic studies in different Russian regions are needed to improve psychotropic therapy safety and to establish evidence-based indications for pharmacogenetic testing in clinical practice.
authors.forename: Dmitriy A
authors.initials: DA
authors.lastname: Sychev
authors.forename: Irina S
authors.initials: IS
authors.lastname: Burashnikova
authors.forename: Ruslan E
authors.initials: RE
authors.lastname: Kazakov
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001480:Basal Ganglia Diseases / Q000188:drug therapy* / Q000378:metabolism; D019389:Cytochrome P-450 CYP2D6 / Q000235:genetics* / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D010865:Pilot Projects; D011110:Polymorphism, Genetic / Q000235:genetics*; D012426:Russia
chemical_list: D014150:Antipsychotic Agents; D019389:Cytochrome P-450 CYP2D6