No association between polymorphisms in four serotonin receptor genes, serotonin transporter gene and alcohol-related suicide.

BACKGROUND Serotonin (5-HT) is an important neurotransmitter with wide-ranging functions. Its disfunction in the central nervous system seems to play an important role in many psychiatric disorders and suicidal behavior. The objective of this study was to examine the association between polymorphisms in different serotonin receptor genes (HTR): HTR1A (polymorphism -1019C>G), HTR1B (polymorphisms 861G>C and -161A>T), HTR1F (polymorphism -78C>T) and HTR2A (polymorphism -1420C>T), and serotonin transporter gene (5-HTT) (polymorphism LPR in promoter and VNTR in the second intron), and completed alcohol-related suicide, as well as between alcohol-dependent suicide victims. SUBJECTS AND METHODS The study subjects were 373 Slovenian suicide victims (mean age ± SD: 48.8 ± 17.7 years) autopsied in the years 2002 through 2005. During autopsy venous blood was drawn, and afterwards DNA extraction and alcoholimetric analysis were performed. Relatives of 79 suicide victims were interviewed using a semi-structured questionnaire designed according to Slovenian cultural and economic conditions. They provided information about the alcohol abuse of the suicide victims. Amongst the suicide victims were 25 alcohol misusers and 54 non-misusers. RESULTS Association between polymorphisms in the selected serotonin receptor genes, transporter gene and completed alcohol-related suicide, as well as between alcohol-dependent suicide victims was not established. CONCLUSIONS Present results suggest that selected polymorphisms of the 5-HT receptor genes and transporter gene are not involved in genetic susceptibility to completed suicide under acute influence of alcohol or among alcohol-dependent individuals, but further studies in a larger sample are needed.