Hypothesis: a Y-chromosomal gene causes gonadoblastoma in dysgenetic gonads.

The role of the human Y chromosome in the etiology of gonadoblastoma, a gonadal neoplasm, is considered and a two-part model is presented. According to this hypothesis: (1) There is a gene on the Y chromosome that strongly predisposes dysgenetic gonads to develop gonadoblastomas (Page, 1986) and (2) this postulated GBY gene (GonadoBlastoma locus on Y chromosome) has some physiological function in normal males. GBY may, for example, function in or prior to spermatogenesis in normal testes. Y-DNA hybridization analysis of individuals with gonadoblastoma and partial deletions of the Y chromosome should be of use in testing this proposal. To date, such studies suggest that GBY maps to the region that includes deletion intervals 4B to 7, i.e. it is located near the centromere or on the long arm of the Y chromosome.