title: Study of dopamine receptors genes polymorphisms in bipolar patients with comorbid alcohol abuse.
abstract: Alcoholism is present in approximately 40-60% of bipolar patients. This comorbidity between bipolar disorder and alcoholism is high and may result from existence of common genetic factors for the two disorders. In both disorders, dysregulation of the dopaminergic neurotransmission had been implicated. Association analyses revealed several candidate genes acting in the dopaminergic pathway and polymorphisms in those genes that might be associated with both disorders.
  
  
  OBJECTIVE
  The aim of this study was to analyse possible relationship between polymorphisms in the dopaminergic pathway genes (one SNP for each dopamine receptor gene 1-4) and alcohol abuse comorbidity in bipolar patients.
  
  
  METHODS
  We analysed 317 patients with bipolar disorder. In this group, 42 patients were diagnosed with alcohol abuse. The diagnosis was made for each patient by at least two psychiatrists, using structured clinical interviews for DSM-IV Axis I disorders (SCID). The control group consisted of 350 subjects. We performed RFLP analysis of polymorphisms in four genes: DRD1, DRD2, DRD3, and DRD4.
  
  
  RESULTS
  We have not found association of any of the analysed polymorphisms in the dopamine genes in the group of bipolar patients with comorbid alcohol abuse as compared to the control group. In the male group of bipolar patients with comorbid alcohol abuse, we also have not observed any significant differences between the patients and the control subjects.
  
  
  CONCLUSIONS
  Our findings suggest that the analysed polymorphisms of the dopamine genes polymorphisms may not be involved in the shared genetic vulnerability to both, bipolar disorder, and alcohol abuse.
authors.affiliation: Laboratory of Psychiatric Genetics, Poznan University of Medical Sciences, Poznan, Poland. alszczep@amp.edu.pl
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Szczepankiewicz
authors.forename: Monika
authors.initials: M
authors.lastname: Dmitrzak-Weglarz
authors.forename: Maria
authors.initials: M
authors.lastname: Skibínska
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Słopień
authors.forename: Anna
authors.initials: A
authors.lastname: Leszczyńska-Rodziewicz
authors.forename: Piotr
authors.initials: P
authors.lastname: Czerski
authors.forename: Joanna
authors.initials: J
authors.lastname: Hauser
mesh_terms: D000328:Adult; D000437:Alcoholism / Q000235:genetics*; D001714:Bipolar Disorder / Q000235:genetics*; D015897:Comorbidity; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic / Q000235:genetics*; D012150:Polymorphism, Restriction Fragment Length; D011954:Receptors, Dopamine / Q000235:genetics*; D012016:Reference Values
chemical_list: D011954:Receptors, Dopamine