The relationship between stressful life events, the serotonin transporter (5-HTTLPR) genotype and major depression

Regardless of whether our results were based on binary logistic or ordinal regression analyses we found no evidence to support a main effect of 5-HTTLPR, or an interaction between the 5-HTTLPR genotype and stressful life events on major depression, Only 20 % of our subjects were aged below 30 years. It is possible that the effect reported by Caspi and colleagues is specific to young people, in which case our study has much less power in this age group.