Subthreshold depression is linked to the functional polymorphism of the 5HT transporter gene.
BACKGROUND
The functional polymorphism of the serotonin transporter gene (5HTTLPR) has been earlier associated with affective disorders. No research has however been carried out to identify the relationship between this polymorphism and depressive traits and subclinical depressive symptoms within a psychiatrically healthy population.


METHODS
One hundred and twenty-eight female subjects with no lifetime or current history of DSM-IV Axis I disorders participated in the study. All subjects completed the Zung Self-Rating Depression Scale and were genotyped for the 5HTTLPR polymorphism.


RESULTS
Significant differences were found on the Zung SDS and also on the physical-vegetative subscale of the Zung SDS according to both phenotype and genotype. Subjects carrying the s allele scored significantly higher on the Zung SDS and had also significantly higher scores on the physical-vegetative symptom subscale. Furthermore, subjects carrying the ss genotype scored highest and subjects carrying the ll genotype scored the lowest on both scales.


CONCLUSIONS
Subclinical depressive symptoms (i.e. DSM-IV subthreshold depression) are associated with the functional polymorphism of the serotonin transporter gene. The main association between this polymorphism and subclinical depression is primarily carried by the physical symptoms of depression. The s allele of the 5HTTLPR gene is associated with a "low mood endophenotype".
Gonda
Xenia
X
Laboratory of Neurochemistry and Experimental Medicine, National Institute of Psychiatry and Neurology, Huvosvolgyi ut 116, H-1021 Budapest, Hungary.
Juhasz
Gabriella
G
Laszik
Andras
A
Rihmer
Zoltan
Z
Bagdy
Gyorgy
G
D000293:Adolescent; D000328:Adult; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000235:genetics* / Q000523:psychology*; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic / Q000235:genetics*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D012720:Severity of Illness Index
D050486:Serotonin Plasma Membrane Transport Proteins