Familial biochemical and clinical correlates of alcoholics with low platelet monoamine oxidase activity.

This study substantiates previous reports that low platelet MAO activity is associated with alcoholism. The results also indicate that low platelet MAO activity in alcoholic probands is associated with a higher prevalence of psychiatric hospitalization in first-degree family members as well as alcoholism and suicide attempts among alcoholics. Psychiatrically ill family members of the alcoholic probands with low platelet MAO activity also demonstrate low enzyme activity whereas the well family members have normal enzyme activity.