Relevance of normal loci in Yq11 position( q means long arm of chromosome) & normal Spermatogenesis ??

Relevance of  normal loci in Yq11 position( q means long  arm   of chromosome) & normal Spermatogenesis ?? Spermatogenesis  is governed by long arm of the Y chromosome AS such if there is changes in Y chromosome i.e. in the form of Yq11Microdeletion of the azoospermia factor (AZF) region located on the long arm of the Y chromosome (Yq11) is considered the most common genetic cause of male infertility . However, Y microdeletions can be transmitted from infertile fathers to their male offspring, who could also experience infertility, through the procedure of ICSI. Thus, it is important to evaluate Y microdeletions in male infertility before assisted reproduction in order to provide appropriate information to patients.The AZF region is divided into three nonoverlapping subregions called AZFa, AZFb, and AZFc, all of which are required for normal spermatogenesis. Microdeletions in these three regions are associated with various spermatogenetic alterations including Sertoli cell-only syndrome (SCOS), maturation arrest, and hypospermatogenesis. Specifically, microdeletion of AZFa is relevant to complete SCOS and azoospermia. The absence of AZFb is associated with maturation arrest at meiosis, whereas microdeletion of AZFc results in variable clinical and histologic phenotypes, ranging from oligozoospermia to SCOS . Extensive studies have been carried on Y microdeletions in non-obstructive azoospermic and severely oligozoospermic patients, with a reported incidence ranging from 3% to 28%. Therefore, disruption of AZF can be viewed as the most common molecularly diagnosable cause of spermatogenic failure in the setting of non-obstructive azoospermia or severe oligozoospermia .

Recently, the techniques of testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI) have made it possible to help men with azoospermia or severe oligozoospermia to achieve successful fertilizations and pregnancies . However, Y microdeletions can be transmitted from infertile fathers to their male offspring, who could also experience infertility, through the procedure of ICSI. Thus, it is important to evaluate Y microdeletions in male infertility before assisted reproduction in order to provide appropriate information to patients.