Figure 2.

Concordances for monozygotic and dizygotic twins. Prevalence of alcoholism in twins and twin concordance of monozygotic (MZ) and dizygotic (DZ) twins for alcoholism in a study of 8,935 pairs of Swedish male twins. Adapted from data reported by Kendler et al. (1992). Squares demarcate 1 standard error (McGue 1999).

SOURCE: Derived from: 1999 American Psychological Society, figure 1, p. 110. McGue, M. The behavioral genetics of alcoholism. Current Directions in Psychological Science 8(4):109–115, 1999.