Cytological evidence for the location of male-determining and H-Y genes on the short arm of Y chromosome.

Chromosome analysis was performed in a case of mixed gonadal dysgenesis (MGD) with histological demonstration of both testicular structures and Müllerian derivatives. Mosaicism 45,X0/46, X plus a centric fragment was observed. C-, Q- and R-banding techniques show that the fragment has a terminal centromere and that it is derived from the short arm of the Y chromosome from the father. H-Y antigen was also shown to be present in cultured cells. These data demonstrate that both male-determining and H-Y genes are located on the short arm of the Y.