Detection of sperm in men with Y chromosome microdeletions of the AZFa, AZFb and AZFc regions

Abstract

BACKGROUND: Y chromosome microdeletions are associated with severe male factor infertility. In this study, the success rate of testicular sperm retrieval was determined for men with deletions of AZF regions a, b or c. METHODS: AZF deletions were detected by PCR of 30 sequence-tagged sites within Yq emphasizing the AZFa, b and c regions. Semen analysis and diagnostic testis biopsy or testicular sperm extraction (TESE) findings were correlated with the specific AZF region deleted. RESULTS: A total of 78 men with AZF deletions included three with AZFa deletion, 11 with AZFb, 42 with AZFc, 16 with AZFb+c and six with Yq (AZFa+b+c). All men with AZFa, AZFb, AZFb+c and Yq deletions were azoospermic and no sperm were found with TESE or biopsy. Of men with isolated AZFc deletion, sperm were found in 75% (9/12) by TESE and 45% (9/20) on biopsy (56% overall); 62% (26/42) were azoospermic and 38% (16/42) severely oligozoospermic. A total of 7 patients with deletion patterns that included the complete AZFa region and 23 that included the complete AZFb region who underwent TESE or biopsy did not have sperm detected by these surgical measures. CONCLUSIONS: Microdeletion of the entire AZFa or AZFb regions of the Y chromosome portends an exceptionally poor prognosis for sperm retrieval, whereas the majority of men with AZFc deletion have sperm within the semen or testes available for use in IVF/ICSI.