Alpha 1-antitrypsin phenotypes in homosexual men

The alpha 1-antitrypsin (AAT) phenotype was determined by isoelectric focusing in 215 male homosexuals and compared with those in 208 male heterosexuals. The incidence of abnormal phenotypes was 16.3% in the homosexual group which was significantly different (p less than 0.03) than the 8.7% in the heterosexual group. There was no difference in the phenotype distribution between homosexuals who were anti-human immunodeficiency virus reactive and those who were non-reactive. It suggests that investigation into the interplay of factors associated with homosexuality could include genetic as well as psychological and social factors.