Family history status was not significantly related to acute response to alcohol in either cohort. These results support a recent null finding of FH on acute response to an intravenous alcohol challenge in moderate social drinkers (Kerfoot et al., 2013 in press). Although FH has been identified as a predictor of future alcohol-related problems, it is still unclear how it conveys risk. While persons with FH+ have been theorized to be need to drink more to feel the effects of alcohol, support for this relationship in laboratory findings has been inconsistent (Newlin and Thomson 1990; Newlin et al., 2010; Morean and Corbin 2011). That FH status was not related to acute alcohol response in HD may suggest that FH and HD are two risk factors that represent distinct and non-overlapping pathways to early alcohol misuse and eventual AUD (Quinn & Fromme, 2011; King et al., 2011b), or that engaging in frequent binge drinking in late adolescence and young adulthood, regardless of FH status, produces numerous systemic changes that ultimately result in the distinct alcohol response phenotype observed in our two
