RESUMO
Male factors account for nearly 50% of infertilities, among which genetic defects constitute some of the major ones. Microdeletion of the long arm of Y chromosome has been seen in about 7% of infertile men. The importance of these microdeletions lies in the possibility of their occurrence in the off-springs in ART and their de novo appearance. This cross-sectional descriptive-analytical study was performed on 47 individuals with azoospermia or severe oligozoospermia. The cases were recruited when they attended Imam Reza Hospital in Mashad during 2006-2008. Hormone profile, including FSH, was measured and karyotyping, testicular biopsy and Y chromosome microdeletion detection, using 11 pairs of sequence-tagged site [STS method] sets which were specific for AZF and SRY loci, were performed. Three out of four patients with azoospermia had Y chromosome microdeletion [8.5%]. Klinefelter's syndrome and deletion of SRY region were each seen in two patients [4.3%]. Multiple AZF region deletions were seen in 75% of Y chromosome microdeletions and deletions in AZFa, AZFb and AZFc regions were seen in 25%, 75% and 100% of the cases, respectively. The prevalence of AZF deletion in patients with and without FSH abnormality were 17.6% and 3.3%, respectively, however, the differences were not statistically significant [p = 0.125]. In patients with azoospermia and severe oligozoospermia, AZF deletion were 11.1% and 5%, respectively [p = 0.628]. In addition, there were no significant differences in AZF deletion between patients suffering from varicocele or other related disease [p = 1.0]. Family history had no significant effect on AZF deletion [p = 0.239]. Testicular biopsy showed Sertoli-cell-only syndrome in three out of four patients with AZF microdeletions. Male factor infertility is associated with a high incidence of Y chromosome microdeletions and transmission of these defects to the off-springs in ART, aside from their de novo occurrence, seems probable. Therefore, it would be wise to look for microdeletions in cases with severe oligozoospermia or cases with non-obstructive azoospermia. There seems to be a correlation between the prevalence of AZF regional deletions and the degree of spermatogenesis disruption but this finding needs further scientific evidence