Association studies of candidate genes in bipolar disorders

The aim of the investigation was to test genes for predisposition to bipola r affective disorder. Therefore, we studied candidate genes in a sample of unrelated patients (n = 102) and healthy controls (n = 79) of Austrian orig in, searching for a possible association between polymorphic DNA markers of 5 candidate genes (serotonin transporter, 5-HTT;serotonin 2a receptor, 5-H T2a; dopamine D2 receptor, DRD2; dopamine D3 receptor, DRD3; dopamine trans porter, DAT1) and bipolar disorder. There was an association between alleli c and genotypic frequencies of 5-HTT and affection status (p = 0.014 and p = 0.017, respectively). However, after correction for multiple comparisons (Bonferroni), these results did not remain significant. Nevertheless, the f indings might suggest that alterations in the structure of 5-HTT are involv ed in the pathogenesis of bipolar disorder, which could have major implicat ions in treatment. No association between 5-HT2a, DRD2, DRD3, DAT1 and bipo lar disorder was found. Copyright (C) 2000 S. Karger AG, Basel.