Social adversity, the serotonin transporter (5-HTTLPR) polymorphism and major depressive disorder.

Strangeways Research Laboratory and University of Cambridge Department of Public Health and Primary Care, Worts Causeway, Cambridge, UK.
Biological Psychiatry (Impact Factor: 9.47). 03/2006; 59(3):224-9. DOI: 10.1016/j.biopsych.2005.07.014
Source: PubMed

ABSTRACT Recent evidence has suggested that the short allele of the serotonin transporter (5-HTT) gene-linked polymorphic region (5-HTTLPR of the human serotonin gene [SLC6A4]) is associated with increased risk of depressive disorder but only among individuals exposed to social adversity. We report an investigation designed to replicate this finding.
Data were available from a non-clinical sample of 4,175 adult men and women, ages 41-80 years, selected from participants in the European Prospective Investigation into Cancer and Nutrition in Norfolk (EPIC-Norfolk, United Kingdom) study. Evidence of past-year prevalent episodic major depressive disorder (MDD), defined by restricted DSM-IV diagnostic criteria, was assessed through questionnaire. Adverse experiences in childhood and in adulthood (during the five years preceding assessment) were also assessed through self-report. The 5-HTTLPR variant was genotyped according to published protocols.
One-year prevalent MDD criteria were met by 298 study participants. The experience of social adversity (both in childhood and adulthood) was strongly associated with increased rates of past-year prevalent MDD. No gene by environment (GxE) interactions between the 5-HTTLPR genotype, social adversity, and MDD were observed.
This study has not replicated a previous finding of a GxE interaction between the 5-HTTLPR genotype, social adversity, and depression.

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