Mosaic isodicentric Y chromosome harboring intact AZF region in a cryptozoospermic male with normal hormone levels

Dear Editor,Structural aberrations of the Y chromosome,including deletions,ring chromosomes,Y-autosomal or Y-X translocations,isochromosomes,and dicentrics,occur in approximately 0.2%of live births;1 among these,partial deletion in the azoospermia factor(AZF)region of the Y chromosome is a well-characterized cause of nonobstructive severe oligozoospermia and azoospermia.2 Meanwhile,a dicentric Y chromosome,abbreviated as dic(Y),was observed to be exclusively present in males with azoospermia,suggesting more severe negative consequences of the AZF deletion for spermatogenesis.