Serotonin transporter gene polymorphisms, alcoholism, and suicidal behavior.

Area of Science:

• Neuroscience
• Genetics
• Psychiatry

Background:

• Serotonin transmission dysfunction is linked to excessive alcohol consumption and dependence.
• The serotonin transporter gene (5-HTTLPR) polymorphism is associated with various disorders, including alcoholism.
• Investigating 5-HTTLPR in specific alcohol dependence phenotypes, like impulsivity, is crucial.

Purpose of the Study:

• To examine the association between the 5-HTTLPR functional polymorphism and the risk of suicide attempts in male alcohol-dependent individuals.
• To explore the specific role of 5-HTTLPR in the heterogeneity of alcohol dependence phenotypes.

Main Methods:

• Analysis of the 5-HTTLPR functional polymorphism in 110 male alcohol-dependent subjects (DSM-III-R) and 61 controls.
• Subjects were interviewed using the Diagnostic Interview for Genetic Studies.
• Population comprised individuals of French descent for at least two generations.

Main Results:

• The short (S) allele of 5-HTTLPR was not associated with alcohol dependence or comorbid depression.
• A significant association was found between the S allele and an increased risk for suicide attempts.
• A dose-dependent effect of the S allele was observed on the number and severity of suicide attempts, particularly in severe and repetitive attempts.

Conclusions:

• A genetic predisposition, potentially a relative deficiency in serotonin reuptake related to 5-HTTLPR, may interact with mood disorders and alcohol dependence.
• This interaction increases the risk for aggressive and impulsive behaviors, such as suicide attempts.
• The findings highlight the role of specific genetic polymorphisms in modulating the risk of severe outcomes in alcohol dependence.