Serotonin system gene polymorphisms are associated with impulsivity in a context dependent manner

Prog Neuropsychopharmacol Biol Psychiatry. 2012 Oct 1;39(1):182-91. doi: 10.1016/j.pnpbp.2012.06.012. Epub 2012 Jun 23.

Abstract

Impulsivity is a risk factor for adverse outcomes and characterizes several psychiatric disorders and risk for suicide. There is strong evidence that genetic variation influences individual differences in impulsivity, but the details are not yet understood. There is growing interest in better understanding the context dependency of genetic effects that is reflected in studies examining gender specificity, gene×environment interaction and epistasis (gene-gene interaction). In a cross-sectional study we examined whether polymorphisms in six serotonin system candidate genes and the experience of early life trauma (age 0-12) were associated with individual differences in impulsivity in a non-clinical sample of Caucasian university students (N=424). We specifically tested potential gender specific, gene-gene, and gene×environment (early life trauma) effects. In our main analyses with Barratt Impulsiveness Scale (BIS-11) total score, there were significant (i.e. p<.01 and False Discovery Rate <.10) interactions between (1) gender and TPH2 (rs1386483) genotype; (2) gender and HTR2A (rs6313) genotype; and epistatic interactions among (3) 5-HTTLPR and MAOA uVNTR; (4) 5-HTTLPR and rs6313 and (5) HTR1B (rs6296) and rs6313 genotypes. Our results strongly support the explicit investigation of context dependent genetic effects on impulsivity and may help to resolve some of the conflicting reports in the literature.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Adult Survivors of Child Abuse / psychology
  • Cross-Sectional Studies
  • Epistasis, Genetic / genetics
  • Female
  • Gene-Environment Interaction
  • Genetic Association Studies / methods
  • Genetic Association Studies / statistics & numerical data
  • Genotype
  • Humans
  • Impulsive Behavior / genetics*
  • Life Change Events
  • Male
  • Monoamine Oxidase / genetics*
  • Polymorphism, Genetic / genetics*
  • Receptor, Serotonin, 5-HT1A / genetics*
  • Receptor, Serotonin, 5-HT1B / genetics*
  • Serotonin Plasma Membrane Transport Proteins / genetics*
  • Sex Characteristics
  • Tryptophan Hydroxylase / genetics*
  • White People / genetics
  • White People / psychology

Substances

  • HTR1B protein, human
  • Receptor, Serotonin, 5-HT1B
  • SLC6A4 protein, human
  • Serotonin Plasma Membrane Transport Proteins
  • Receptor, Serotonin, 5-HT1A
  • TPH2 protein, human
  • Tryptophan Hydroxylase
  • Monoamine Oxidase