Fisher, H.Cohen-Woods, S.Hosang, G.Uher, R.Powell-Smith, G.Keers, R.Tropeano, M.Korszun, A.Jones, L.Jones, I.Owen, M.Craddock, N.Craig, I.Farmer, A.McGuffin, P.2013-03-252013-03-252012Journal of Affective Disorders, 2012; 136(1-2):189-1930165-03271573-2517http://hdl.handle.net/2440/76229<h4>Background</h4>An interaction between recent stressful life events (SLEs) and a serotonin transporter promoter polymorphism (5-HTTLPR) in depression has been inconsistently reported. Some of this variability may be due to a previous focus on sub-clinical depression, inclusion of individuals at the lower or upper ends of the age-span, or assumptions concerning the degree of dominance of the low expressing allele. Therefore, a large sample of patients with recurrent clinically diagnosed depression and controls screened for absence of depression was utilised to examine the moderating effect of each 5-HTTLPR genetic model on the association between SLEs and severe depressive episodes.<h4>Method</h4>A sample of 1236 recurrent unipolar depression cases and 598 age-matched, never psychiatrically ill controls completed the List of Threatening Experiences Questionnaire to assess the number of SLEs experienced in the 6 months prior to the most severe depressive episode (cases) or interview (controls). DNA extracted from blood or cheek swabs was genotyped for the short (s) and long (l) alleles of 5-HTTLPR.<h4>Results</h4>A greater number of SLEs were reported by cases than controls and this held across all genotypic groups. There was no main effect of 5-HTTLPR on depression and no evidence of interaction between total SLEs and any of the 5-HTTLPR genetic models. The results were the same for men and women.<h4>Limitations</h4>Utilisation of retrospective self-reported SLEs may have reduced the accuracy of the findings and the cross-sectional design prevents causal inference.<h4>Conclusions</h4>This study failed to find evidence of gene-environment interplay in recurrent clinical depression.enCopyright © 2011 Elsevier B.V. All rights reserved.Stressful life eventsUnipolar depressionRecurrentGene–environment interaction5-HTTLPRJournal article002012410510.1016/j.jad.2011.09.0160002984517000272-s2.0-8485705160621964Cohen-Woods, S. [0000-0003-2199-6129]