No abstract

The aim of this study was to determine the appropriate tag sequence tagged site (STS) associated with azoospermia. We evaluated the incidence of Y chromosome microdeletions in Tunisian infertile male patients by polymerase chain reaction using 14 STSs in the azoospermia factor (AZF) region of Yq11. A logistic regression analysis was performed to test the association of STSs with semen quality. Haploview version 3.11 was used to identify the possible blocks of deletion involving a minimum number of STSs and that can be used to tag the deletion block in future analysis. Using the 14 STSs, 48% infertile patients (102 of 210) had microdeletions of Y chromosome but, following the European Academy of Andrology guidelines, only 16% of patients had microdeletions. A statistically significant difference was found with some STSs for azoospermia and oligozoospermia. A candidate combinaison composed of 4 STSs (RBMY-sy157-sy84-sy130) was associated with azoospermia in a Tunisian population. According to this study, this tag can be used in the screening of Y chromosome microdeletions before assisted reproduction treatment in a Tunisian population.

Azoospermia factor (AZF) deletions were associated with severe oligospermia and azoospermia with testicular histologies varying from maturation arrest (MA) to Sertoli cell-only (SCO) phenotypes. Abnormal androgen receptor (AR) structure or function has also been implicated in male infertility. To assess the contribution of these genetic defects to azoospermic patients, 19 Tunisian men with SCO (n = 13) or MA (n = 6) were enrolled in this study. Using immunohistochemistry method, we evaluated the expression of AR in testicular biopsy for the two phenotypes. PCR with primers flanking the AR-(CAG)n region and direct sequencing were used to determine AR-(CAG)n length. And PCR amplification of 14 sequence-tagged sites (STSs) located at Yq was used to determine the rate and extent of Y microdeletions. We found a significant difference of the AR expression between SCO and MA cases. Hence, this expression in the testis depends on the status of spermatogenesis. However, we did not find any relationship between the (CAG) repeat and the testicular histology (neither for SCO nor MA). On the other hand, we found a high frequency of AZF deletions (46.2%) in SCOS and in MA (50%). The present results also suggest the contribution of Y chromosome microdeletions in SCO and MA pathogenesis.

Our work showed the absence of relationship between Y chromosome microdeletions and varicocele development and the association of the two factors, independently, with sperm production defect.