Serotonin transporter gene polymorphisms, alcoholism, and suicidal behavior.
BACKGROUND
Dysfunction of serotoninergic transmission could predispose to excessive alcohol consumption and dependence. The functional polymorphism of the serotonin transporter gene (5-HTTLPR) has been associated with different disorders, including alcoholism. Considering the likelihood of heterogeneity in the "alcohol dependence" phenotype, 5-HTTLPR may be more specifically implicated in subsamples of patients or in related traits of alcoholism, such as impulsivity.


METHODS
We analyzed the role of this functional polymorphism in the risk for suicide attempt in a population of male alcohol-dependent subjects. One hundred ten male alcohol-dependent patients (DSM-III-R criteria), French for at least two generations, were personally interviewed with the Diagnostic Interview for Genetic Studies and compared with 61 unaffected blood donors.


RESULTS
The "short" (S) allele of the 5-HTTLPR appeared to be unrelated to alcohol dependence and comorbid depression in our sample, but was found associated with an increased risk for suicide attempts. This association was predominantly observed in severe and repetitive suicide attempts, with a significant dose effect of the S allele (0, 1, or 2) on the number and the severity of suicide attempts.


CONCLUSIONS
Mood disorders and alcohol dependence may interact with a genetic (relative) deficiency in serotonin reuptake, thereby increasing the risk for aggressive/impulsive behaviors such as suicide attempts.
Gorwood
P
P
Service de Psychiatrie, Hôpital Louis Mourier, Colombes, France.
Batel
P
P
Adès
J
J
Hamon
M
M
Boni
C
C
D000328:Adult; D000437:Alcoholism / Q000235:genetics*; D000483:Alleles; D002352:Carrier Proteins / Q000235:genetics*; D015870:Gene Expression / Q000235:genetics*; D005824:Genetics, Behavioral; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics*; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D016133:Polymerase Chain Reaction / Q000379:methods; D011110:Polymorphism, Genetic / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D012307:Risk Factors; D012701:Serotonin / Q000235:genetics*; D050486:Serotonin Plasma Membrane Transport Proteins; D013406:Suicide, Attempted / Q000523:psychology*
D002352:Carrier Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D012701:Serotonin