High level of harm avoidance is associated with SLC6A4 functional haplotypes in alcohol dependent subjects

The serotonin transporter gene (SLC6A4) encodes a trans-membrane protein (5-HTT) playing an important role in regulating serotonergic neurotransmission, which is known to be involved in many psychiatric disorders. A polymorphism in the transcriptional control region containing long (L) and short (S) variants (5-HTTLPR) as well as alleles of the variable number tandem repeats (VNTR) region were demonstrated. Higher serotonin levels among carriers of the S-allele might exhibit increased liability of serotonin mediated psychopathology like anxiety and depression and may impair social skills reflected by harm avoidance. In our study we analyzed the data of 368 alcohol-dependent unrelated German individuals. No significant association was found between history of depression and 5-HTTLPR (F=0,42, p=0,65, df=2) as well as between history of depression and VNTR (F=0,24, p=0,91, df=2). As harm avoidance is often associated with history of depression the temperament and character inventory (TCI) was employed. Regarding the TCI temperament and character scale scores, no significant association was found between harm avoidance and this genetic variant 5-HTTLPR (F=0,55, p=0,57, df=2) and between harm avoidance and VNTR (F=0,39, p=0,81, df=2). Significant associations were detected between Babors Type A/B and history of depression (F=17,70, p=0,00, df=1) and harm avoidance (F=7,04, p=0,00, DF01). Haplotype analysis showed significant relationship between high level of harm avoidance and