Maternal inheritance of alcohol abuse. Cross-fostering analysis of adopted women.

The inheritance of alcohol abuse was studied in 913 Swedish women adopted by nonrelatives at an early age. There was a threefold excess of alcohol abusers among the adopted daughters of alcoholic biological mothers compared with other daughters. In addition, there was an excess of alcohol abuse among the daughters of biological fathers with alcohol abuse that was mild and not associated with criminality. However, fathers with extensive treatment for both alcoholism and criminality had no excess of alcoholic daughters. This confirms the heterogeneity among alcoholics noted in earlier work with adopted sons, which found that the latter type of criminal alcoholics also had no excess of alcoholic mothers. Imitation of alcohol abuse by adoptive parents did not increase later alcohol abuse by adopted women. The importance of nonfamilial environments and maternal effects is demonstrated for alcohol abuse in women.