Sex differences in alcohol‐related outcomes have also been examined in numerous twin studies. For example, in the first population‐based twin study of alcoholism in the U.S., Prescott and colleagues 104 found substantially higher concordance among MZ than DZ pairs across several definitions of alcohol abuse and dependence, there was no difference in the genetic liability between women (55‐66%) and men (51‐56%). A correlation of 0.50 was projected for same‐sex DZ twin pairs; whereas, they reported genetic correlations of 0.20 to 0.24 for opposite‐sex pairs, which indicates that there are different genetic influences for men and for women. 104 In contrast to earlier work, a recent review concluded that although there are numerous sex differences for alcohol‐related outcomes, the genetic influence on these outcomes is the same across sexes. 5 Future studies should aim to address these conflicting findings.
