Introduction: Male infertility has a heterogeneous etiology, most commonly caused by spermatogenesis disorders. Genetic factors explain about 30% of cases of male infertility associated with azoospermia and severe oligozoospermia. Y microdeletion is the most frequent known molecular genetic cause of severe impairment of spermatogenesis. The Purpose: To evaluate the frequencies and types of Y chromosomal microdeletion of the AZF regions, before Assisted Reproductive Techniques (ART) and to compare our results with other reports. Materials and methods: Infertile men were investigated during genetic counseling among infertile couples referred for ART treatment. The study group consisted of 98 men with azoospermia. They were between 21 and 44 years old (median age - 33 years). Semen analysis in all infertile men was assessed according to WHO, 2010. G-banding of metaphase chromosomes karyotype analysis were performed in all azoospermic patients. Genomic DNA was isolated and used to analyze AZF microdeletions by PCR. The regions and sequence-tagged sites of AZFa (sY84, sY86, DBY1, sY620), AZFb (sY117, sY127, sY134, SY143), and AZFc (sY254, sY255, sY153, SY158) were sequenced by multiplex PCR. The detections of sY14 (SRY) and ZFX/ZFY were employed as internal controls. Ten non-obstructive azoospermic men had Y chromosomal microdeletions. Six Y-microdeleted men underwent microsurgical observation of testicular architecture and quantitative histology of spermatogenesis in a strip of testicular tissue. The results were compared with the different type of Y microdeletion. Results: Deletions of Y chromosome were revealed in 10 (9,8%) of 98 patients with azoospermia. Deletions of AZFc - sY153, sY158, sY254 and sY255 locus were observed in five of ten azoospermic patients 50%. In two patients of ten 20% were detected with deletion of AZFb region, deleted markers were sY117, sY127, sY134, sY143. Deletions affecting both AZFb and AZFc loci were found in two patients 20%, with non-obstructive azoospermia. In only one case (1/10) 10% were detected microdeletions in each region of AZF: AZFa-sY84, sY86, sY620, DBY1; AZFb- s Y117, sY127, sY134, sY143; AZFc- sY153, sY158, sY254, sY255; and presence of the SRY gene, in the patient with XX male syndrome. AZFa deletions have not been detected in either patient. In all men with AZF microdeletions of the Y chromosome we found severe spermatogenic defects: however, we also didn’t found, in all of them, mature sperm sufficient for ICSI. The patients were advised to use sperm from the donor for ICSI and IVF. Conclusions: Y chromosome microdeletions screening is important to define the aetiology of men with severe spermatogentic defects. This is important to provide a firm diagnosis and more effective solutions to couples with longstanding infertility, before ART.
