Cytogenetic studies in a Y-to-X translocation observed in three members of one family, with evidence of infertility in male carriers.

A family is reported in which the mother and two sons are carriers of a Y-to-X translocation, der (X)t(X;Y) (p22;q11). All the the three carriers have short stature and disproportion of extremities, but otherwise normal phenotype. One of the sons, the propositus, has been affected with schizophrenia. Evidence was obtained that male carriers are probable sterile; both sons aged 26 and 30 years had azoospermia and the biopsied specimens of the testis had histologic pictures showing spermatogenetic arrest. The mother was H-Y weakly positive, and the normal X chromosome was inactivated in the majority of the cells analyzed. Dermatoglyphics of the three carriers were unusual and dissimilar to the features of Turner's syndrome. The clinical and cytogenetic findings in the present study are compared with those of the previously reported familial cases, and the genetic background causing phenotypic abnormalities in the male and female carriers is discussed.