The combination of alcohol dependence and depression (i.e., the AAD phenotype) appears to run in families, as demonstrated by an analysis of first-degree relatives of alcoholic probands with or without depression and first-degree relatives of control subjects. This analysis found that AAD occurred in 15.9 percent of first-degree relatives of probands with AAD (489 out of 3,069 people), compared with 11.7 percent of first-degree relatives of probands with alcoholism alone (287 out of 2,462) and 3.6 percent of first-degree relatives of control subjects (42 out of 1,164). Thus, the prevalence of AAD was significantly greater among the first-degree relatives of probands with AAD than among relatives of probands with alcoholism alone or relatives of control subjects (Nurnberger et al. 2001).
