Deletion of Y chromosome involving the DAZ (deleted in azoospermia) gene in XX males

The testicular histology and the presence or absence of 32 Y DNA loci was i nvestigated, with a focus on the long arm of Y chromosome (Yq) interval 6, by means of a polymerase chain reaction strategy in 2 XX males. Seminiferou s tubules lined by only Sertoli cells and a slight thickening of tubular wa lls were observed. The men showed an absence of 32. Y DNA loci. These facts suggest that severe spermatogenic impairment is caused by deletions of Yq interval 6 in XX males.