ACE and major depressive disorder: The main findings of our study indicate that there was a time-dependent decline in depressive symptomatology from study inclusion to 2-year follow-up and that the persistence of depressive symptoms was linked to genetic variations in the ACE and 5-HTT genes, as carriers of the ACE D/D, 5-HTTLPR I/I haplotype had significantly higher self-rated depression scores after 2 years as compared to the other haplotype carriers.