The findings showed that adoptive mothers tended to report more behavioral problems of their children according to specific individual features; mothers who showed more temperamental features of negative affectivity-NA (more sensitivity to a broad spectrum of negative stimuli, fear, anxiety and sadness, depression and aggravation, and frustration), and who were also carriers of dopamine 7r allele of DRD4, showed the highest evaluation of the presence of behavioral problems in their just adopted children. This evidence concerns the gene DRD4 and major depressive disorder.