Dopamine D2 receptor genotype is associated with increased mortality at a 10-year follow-up of alcohol-dependent individuals

Abstract

Aims: Because the TAQ1 A1 allele may be associated with alcohol-related medical illnesses, and medical illnesses in alcohol-dependent individuals are associated with increased mortality, we test the hypothesis that the TAQ1 A1 allele of the DRD2 gene is associated with increased mortality in alcohol-dependent individuals. Methods: Following an index treatment episode, a 10-year follow-up study in 366 alcohol-dependent individuals was performed. The TAQ1 A1/A2 DRD2 genotype and allele frequencies were compared between those deceased and those still living at the 10-year point. In addition, the genotype and allele frequencies of these alcohol-dependent individuals were compared to that in 578 control subjects. Results: The prevalence of the A1 allele differed between the deceased and living patients and the controls: 47% of the deceased were A1+, compared to 37% of the living patients and 32% of the controls. The frequency of the TAQ1 A1/A2 genotype also differed between the groups. Thus, 43% had the A1/A2 genotype in comparison with 32% in the living patients and 29% in the controls. The TAQ 1 A1 allele frequency differed between the groups. The frequency of A1 allele was 25% in the deceased patients compared to 21% in the living patients and 17% in the controls. Conclusion: The TAQ I A1 allele of the DRD2 gene (or DRD2 gene region) was associated with increased mortality over a 10-year period in alcohol-dependent individuals. © The Author 2009. Published by Oxford University Press on behalf of the Medical Council on Alcohol.