Moreover, obesity in pregnant patients increases the odds of antenatal and postpartum depression through a complex genetic crosstalk between polymorphisms of serotonin (HTR2A), catecholamine (COMT and MAOA), HPA-axis (CRHR1), and oestrogen receptor genes [86,105]. The gene discussed is COMT; the disease is obesity due to melanocortin 4 receptor deficiency.