Enhancing the gene-environment interaction framework through a quasi-experimental research design: evidence from differential responses to September 11.
This article uses a gene-environment interaction framework to examine the differential responses to an objective external stressor based on genetic variation in the production of depressive symptoms. This article advances the literature by utilizing a quasi-experimental environmental exposure design, as well as a regression discontinuity design, to control for seasonal trends, which limit the potential for gene-environment correlation and allow stronger causal claims. Replications are attempted for two prominent genes (5-HTT and MAOA), and three additional genes are explored (DRD2, DRD4, and DAT1). This article provides evidence of a main effect of 9/11 on reports of feelings of sadness and fails to replicate a common finding of interaction using 5-HTT but does show support for interaction with MAOA in men. It also provides new evidence that variation in the DRD4 gene modifies an individual's response to the exposure, with individuals with no 7-repeats found to have a muted response.
a La Follette School of Public Affairs , University of Wisconsin-Madison , Madison , Wisconsin , USA.
Jason M
JM
Fletcher
D000293:Adolescent; D000328:Adult; D003863:Depression / Q000209:etiology / Q000235:genetics* / Q000523:psychology; D050483:Dopamine Plasma Membrane Transport Proteins / Q000235:genetics; D059647:Gene-Environment Interaction; D006801:Humans; D008297:Male; D008995:Monoamine Oxidase / Q000235:genetics; D011569:Psychiatric Status Rating Scales; D017448:Receptors, Dopamine D2 / Q000235:genetics; D050638:Receptors, Dopamine D4 / Q000235:genetics; D012107:Research Design; D047851:September 11 Terrorist Attacks / Q000523:psychology*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics; D055815:Young Adult
C581293:DRD2 protein, human; C493599:DRD4 protein, human; D050483:Dopamine Plasma Membrane Transport Proteins; D017448:Receptors, Dopamine D2; C493214:SLC6A3 protein, human; C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D050638:Receptors, Dopamine D4; D008995:Monoamine Oxidase