The Frequency of Chromosomal Abnormalities and Y Chromosome Microdeletions in Infertile Non-Obstructive Azoospermic and Severe Oligozoospermic Males

Abstract

Purpose: To estimate the frequency and types of both chromosomal abnormalities and Azoospermia Factor (AZF) microdeletions among patients with non-obstructive azoospermia (NOA) and severe oligozoospermia (SOZ) with sperm count less than 5 million/ml. Methods: Karyotyping was performed for all 1127 patients, whereas AZF microdeletions assay was done for 811 patients including 653 NOA and 158 SOZ by multiplex polymerase chain reaction (PCR). All patients were subjected to clinical examination, scrotal duplex ultrasound and hormonal evaluations. Results: The frequency of chromosomal abnormalities was 14.4%, higher in NOA than SOZ men (22.6% versus 3.7%). Numerical chromosomal abnormalities were higher than structural type (11.8% versus 2.4%). Klinefelter syndrome (KS) represented 11.2% of the total chromosomal and 94.1% of sex chromosomal abnormalities. AZF microdeletions were higher in NOA than SOZ (6.1% versus 3.16%). AZFc microdeletions represented the most frequent finding: 31/45 (68.9%), followed by AZFbc: 7/45(15.6%), AZFb: 4/45 (8.8%) and AZFa: 3/45 (6.7%). All patients with AZFa (3), AZFb (4) and AZFbc (7) deletions were NOA, while 26/31(83.87%) with isolated AZFc deletion were NOA and 5/31(16.13%) were SOZ. Conclusion: In according to the results shown, we emphasize the importance of karyotyping and AZF microdeletions analysis in such groups. Counseling for such patients before ARTs is warranted to decrease the risk of transmitting genetic abnormalities to off spring.