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.Conclusion
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.