A Study of Alcoholism in Half Siblings

The authors studied the incidence of alcoholism in children who had an alcoholic biologic parent but who were raised by nonalcoholic parent figures and in children who did not have an alcoholic biologic parent and who were raised by alcoholic parent figures. Similarly, children with and without alcoholic biologic parents who shared their childhood homes with alcoholic probands were compared. For each comparison of genetic and environmental factors, the genetic factor seemed to he more closely associated with the development of alcoholism.