Background The human Y chromosome is essential for human sex determination and male germ cell development and maintenance. In 1996, Vogt et al. identified three recurrently deleted regions in Yq11 termed the azoospermia factor (AZF). The AZF region is subdivided into three non-overlapping sub-regions called AZFa, AZFb and AZFc and microdeletion in these regions is the most important etiology of...