Purposes To investigate the frequency and type of both chromosomal abnormalities and Y chromosome microdeletions and analyze their association with defective spermatogenesis in Chinese infertile men. Methods This is a single center study. Karyotyping using G-banding and screening for Y chromosome microdeletion by multiplex polymerase chain reactio(PCR)were performed in 200 controls and 1,333 infertile men, including 945 patients with non-obstructive azoospermia and 388 patients with severe oligozoospermia. Results Out of 1,333 infertile patients, 154(11.55%) presented chromosomal abnormalities. Of these, 139 of 945 (14.71%) were from the azoospermic and 15 of 388 (3.87%) from the severe oligozoospermic patient groups. The incidence of sex chromosomal abnormalities in men with azoospermia was 11.53% compared with 1.03% in men with severe oligozoospermia (P < 0.01). Also 144 of 1,333 (10.80%) patients presented Y chromosome microdeletions. The incidence of azoospermia factor(AZF) microdeletion was 11.75% and 8.51% in patients with azoospermia and severe oligozoospermia respectively. Deletion of AZFc was the most common and deletions in AZFa or AZFab or AZFabc were found in azoospermic men. In addition, 34 patients had chromosomal abnormalities among the 144 patients with Y chromosome microdeletions. No chromosomal abnormality and microdeletion in AZF region were detected in controls. Conclusions There was a high incidence (19.80%) of chromosomal abnormalities and Y chromosomal microdeletions in Chinese infertile males with azoospermia or severe oligozoospermia. These findings strongly suggest that genetic screening should be advised to infertile men before starting assisted reproductive treatments.

ABSTRACT. The purpose of this study was to detect chromosomal aberrations and azoospermia factor (AZF) microdeletions in male patients with reproductive problems and to summarize related clinical features to provide reliable information for evaluating prenatal and preimplantation diagnoses. A large cohort of 5083 men with various phenotypes of male infertility was analyzed via G-banding karyotyping, and Origin 8.0 was used to analyze the prevalence of abnormalities. Additionally, patients with azoospermia, oligozoospermia, and oligoasthenozoospermia were analyzed using multiplex polymerase chain reaction to detect microdeletion in the AZF. We identified 387 patients with abnormal karyotypes, and the ratio was 7.61%. Among them were 175 patients with Klinefelter's syndrome, which was the most common numerical chromosomal abnormality and accounted for 45.22% of all chromosomal aberrations. The frequencies of increased satellites, balanced translocations, and Robertsonian translocations were 6.47, 7.00, and 3.62%, respectively. Multiplex polymerase chain reaction performed in 810 cases with azoospermia, oligozoospermia, and oligoasthenozoospermia found a ratio of AZF microdeletions of 4.94%. The finding suggests that chromosomal 6513 ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 12 (4): 6512-6520 (2013) Infertility and genetic defects in Chinese male partners abnormalities and AZF deletion are main factors that result in male infertility. Detecting these common genetic variations is necessary in infertile men seeking assisted reproductive technology.