Familial 46,XX males coexisting with familial 46,XX true hermaphrodites in same pedigree.

Reported here is a family with which 46,XX males and 46,XX true hermaphrodites coexist. The propositus was a paternal uncle with 46,XX true hermaphroditism. One of his brothers fathered a 46,XX daughter with true hermaphroditism; a second brother fathered two 46,XX males. Both fathers have normal male karyotypes and phenotypes. No evidence for chromosomal mosaicism or any additional chromosomal abnormalities was obtained. We conclude that inheritance of the abnormality is most likely via paternal transmission of an autosomal testis-determining factor. This family provides evidence to support the hypothesis that 46,XX true hermaphrodites and 46,XX males represent alternative manifestations of the same genetic defect.