The GxE interaction between 5-HTTLPR genotype and environmental adversities on the development of depression appears to be a function of several other variable conditions, and also seems to be an age dependent effect as it is reported as a significant finding in studies in young adults but not in adolescents or the elderly [14]. Based on our results, 5-HTTLPR is strongly relevant in older adults (>30) only in the presence of high number of RLE suggesting that tonic effect of this polymorphism might weaken with age but robust stress could still elicit phasic effects. As the incidence of depression is also age-dependent, it is not unlikely that in different ages and stages of development different factors play a role in the development of depression, and thus this risk is also influenced by different genetic factors.
