MAOA and major depressive disorder: We suggest that the common factor for MAOA and other related genetic variations within the monoaminergic system (Iofrida et al. 2014) has a general impact on the social emotion regulation system, which in different studies may be conceptualized as depression (Beach et al. 2010; Naoi et al. 2017), impulsivity (Chester et al. 2015), alcohol consumption (Nilsson et al. 2007, 2008, 2010; Bendre et al. 2017), aggression and ASB (Kim-Cohen et al. 2006; Byrd and Manuck 2014).