Molecular analysis of CAG repeat length of the androgen receptor gene and Y chromosome microdeletions among Jordanian azoospermic infertile males

Abstract

Assisted reproductive technology is a common procedure which helps millions of couples who suffer fertility problems worldwide every year. Screening for genetic abnormalities prior to such procedure is very important to prevent the transmission of harmful genetic mutations to future generations. Microdeletions within the azoospermia factor (AZF) region of the Y chromosome and the expansion of the CAG trinucleotides in the androgen receptor (AR) gene are among the susceptible causes of male infertility in different ethnic groups. Such association has never been studied in Jordan. In this study, we compared CAG repeat length between azoospermic infertile and normospermic fertile Jordanian males and we also screened the frequency of Y chromosome microdeletions in the same cohort. The study included 142 nonobstructive azoospermic cases and 145 normospermic controls. Results have shown that the median CAG repeat length in the azoospermic group is 19 ± 2 compared to 19 ± 1.5 (p = .6262) in the control group. Deletions within the Y chromosome AZF region were detected in 7 of 142 cases (4.93%) and no deletions were seen in the control group. The results of this study confirm the importance of the AZF region in normal spermatogenesis, whereas it shows no link between the length of CAG repeats in the AR gene and male azoospermia in Jordanian group examined.

Keywords: CAG repeats; androgen receptor; genetics; male infertility.