Individuals with a FH of alcohol dependence have been shown to have disproportionately high rates of trauma exposure and subsequent PTSD compared to individuals without a FH of dependence. For example, one study demonstrated that mother's alcohol dependence status was positively associated with offspring PTSD (Bender, Meyers, McCutcheon, & Bucholz, 2016). This may be due to adverse aspects of the home environment, like having an abusive or neglectful parent or relative (Breslau et al., 2013), as previous studies have demonstrated that having parents with alcohol use problems increases risk for exposure to a traumatic event (Breslau et al., 2013; Dube et al., 2001; Meyers et al., 2014). Further, individuals with a FH of alcohol dependence are at risk, not just because of their environment, but also because of their genetic risk for alcohol dependence, which shares a substantial overlap in genetic influences with PTSD. Studies have shown that genetic influences on PTSD may be around 30%–40% (Banerjee, Morrison, & Ressler, 2017; Nugent, Amstadter, & Koenen, 2008; Stein, Jang, Taylor, Vernon, & Livesley, 2002; True et al., 1993) and alcohol dependence
