1999; Kaufman et al. 2006). We observed one significant three-way interaction of sex, genotype, and childhood trauma on the LEIDS-R RAV scale. Specifically, an association between risk aversion scores and the

high MAOA expression variant was found only in women with a history of childhood trauma. The RAV scale measures the tendency to avoid not only risk but also interpersonal conflict and is the opposite of aggression. As the HH variant of the MAOA genotype is associated with increased aggression, we may speculate that the observed association Inhibitors,research,lifescience,medical between the MAOA-HH variant and risk aversion suggests that in the context of an early adversity, increased risk aversion behavior in HH homozygotes may be a Inhibitors,research,lifescience,medical compensatory mechanism for increased feelings of aggression.

Another explanation of increased R406 aggression in combination with increased risk aversion in the context of early adversity is that MAOA-HH girls who show more aggression during early childhood may have experienced increased punishment for their aggression by their parents Inhibitors,research,lifescience,medical or caretakers, thus learning to avoid certain behaviors to avoid punishment or abuse. However, we did not have sufficient information to test for possible mechanisms accounting for these effects. Individuals who had experienced trauma in childhood had higher HOP reactivity scores than individuals without any history of childhood trauma, irrespective of sex or genotype. Interestingly, HOP reactivity has been found to be a predictor of risk for suicidal ideation or attempt in formerly and currently depressed samples

(Williams Inhibitors,research,lifescience,medical et al. 2008; Antypa et al. 2010). In addition, childhood trauma has been shown to be a predictor of suicidality (Beautrais et al. 1996; Bernet and Stein 1999; Johnson et al. 1999; Dube et al. 2001; Heim and Nemeroff 2001; Agerbo et al. 2002; Brent Inhibitors,research,lifescience,medical et al. 2002). Since our sample comprises healthy individuals, this study extends these observations, suggesting that childhood trauma may set the stage for tendencies toward thoughts of hopelessness. This might in turn lead to suicidal ideation, especially in the context of further Terminal deoxynucleotidyl transferase genetic susceptibility or further stressors. The current study has some limitations, one of them being the relatively small number of men in the sample. Therefore, we cannot rule out the possibility that the lack of effects in men is due to a type II error. Indeed, Williams et al. (2009) found in a healthy sample that MAOA-L men had higher antisocial trait scores than men with the MAOA-H genotype, while no such difference was found in women. Notably, the majority of Williams’ et al. sample consisted of men (67%). In interpreting our results, we should thus consider the possibility that the lack of results in men in the current sample may be due to its smaller size.