Neuroticism mediates the association of the serotonin transporter gene with lifetime major depression.
OBJECTIVE
An association between a polymorphism in the serotonin transporter gene (5HTT-LPR) and the personality trait of neuroticism has been reported. We sought to address the question of whether trait neuroticism mediates the putative association between this polymorphism and lifetime major depression in adults drawn from the general population.


METHODS
Two hundred and fifty-one participants completed the Eysenck Personality Questionnaire and an adapted version of the depression section of the Structured Clinical Interview for DSM-III-R diagnosis, modified for implementation by a self-report questionnaire. A path method was applied to assess the mediator effect of neuroticism on the association between 5HTT-LPR genotype and lifetime major depression.


RESULTS
5HTT-LPR genotype was significantly associated with both neuroticism (p=0.02) and lifetime major depression (p=0.04), and neuroticism with lifetime major depression (p<0.001). Neuroticism accounted for 42.3% of the effect of 5HTT-LPR genotype on lifetime major depression, indicating possible mediation (p<0.001).


CONCLUSIONS
These results suggest that neuroticism mediates the association between 5HTT-LPR genotype and lifetime major depression, consistent with models of the aetiology of depression which suggest that anxiety-related personality traits represent a substantial risk factor for affective disorder.
Munafò
Marcus R
MR
Department of Experimental Psychology, University of Bristol, Bristol, UK. marcus.munafo@bris.ac.uk
Clark
Taane G
TG
Roberts
Kate H
KH
Johnstone
Elaine C
EC
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D016009:Chi-Square Distribution; D003865:Major Depressive Disorder / Q000150:complications / Q000235:genetics* / Q000523:psychology; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D009497:Neurotic Disorders / Q000150:complications / Q000235:genetics* / Q000523:psychology; D010551:Personality / Q000235:genetics*; D011110:Polymorphism, Genetic; D011159:Population Surveillance; D012307:Risk Factors; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*
D050486:Serotonin Plasma Membrane Transport Proteins