DETEKSI DELESI GEN DAZ (Deleted in AZoospermia) PADA PRIA AZOOSPERMIA DENGAN METODE PCR (Polymerase Chain Reaction)

At this time the case of azoospermia is quite common in infertile men. Azoospermia is a condition where the semen does not contain sperm. Many causes azoospermia, including the deletion of a gene at the locus that is located on the Y chromosome long arm (YQ) known as AZF gene (Azoospermia Factor). One of the genes in the AZF region are genes that AZFc DAZ (Deleted in Azoospermia). The purpose of this study was to detect the presence of the DAZ gene deletions in men with azoospermia cases using PCR (Polymerase Chain Reaction). The study design was descriptive. Venous blood samples with EDTA anticoagulant taken from 10 men azoospeermia then extracted to obtain DNA. DNA samples were then carried out PCR with primers DAZ. The PCR products were separated by electrophoresis in 2% agarose gel and visualized using UV translluminator. Of the 10 samples, four patients including DAZ gene deletion was detected experience while the other six do not experience DAZ gene deletions. It concluded that found their DAZ gene deletions in men with azoospermia using the PCR method.

DETEKSI DELESI GEN DAZ (Deleted in AZoospermia) PADA PRIA AZOOSPERMIA DENGAN METODE PCR (Polymerase Chain Reaction)

At this time the case of azoospermia is quite common in infertile men. Azoospermia is a condition where the semen does not contain sperm. Many causes azoospermia, including the deletion of a gene at the locus that is located on the Y chromosome long arm (YQ) known as AZF gene (Azoospermia Factor). One of the genes in the AZF region are genes that AZFc DAZ (Deleted in Azoospermia). The purpose of this study was to detect the presence of the DAZ gene deletions in men with azoospermia cases using PCR (Polymerase Chain Reaction). The study design was descriptive. Venous blood samples with EDTA anticoagulant taken from 10 men azoospeermia then extracted to obtain DNA. DNA samples were then carried out PCR with primers DAZ. The PCR products were separated by electrophoresis in 2% agarose gel and visualized using UVtranslluminator. Of the 10 samples, four patients including DAZ gene deletion was detected experience while the other six do not experience DAZ gene deletions. It concluded that found their DAZ gene deletions in men with azoospermia using the PCR method

Age-related and photoperiodic variation of the DAZ gene family in the testis of the Syrian hamster (Mesocricetus auratus)

SummaryThe Deleted in AZoospermia (DAZ) gene family regulates the development, maturation and maintenance of germ cells and spermatogenesis in mammals. The DAZ family consists of two autosomal genes, Boule and Dazl (Daz-like), and the Daz gene on chromosome Y. The aim of this study was to analyze the localization of DAZL and BOULE during testicular ontogeny of the seasonal-breeding Syrian hamster, Mesocricetus auratus. We also evaluated the testicular expression of DAZ family genes under short- or long-photoperiod conditions. In the pre-pubertal and adult testis, DAZL protein was found mainly in spermatogonia. BOULE was found in the spermatogonia from 20 days of age and during the pre-pubertal and adult period it was also detected in spermatocytes and round spermatids. DAZL and BOULE expression in spermatogonia was strictly nuclear only in 20-day-old hamsters. We also detected the novel mRNA and protein expression of BOULE in Leydig cells. In adult hamsters, Dazl expression was increased in regressed testis compared with non-regressed testis and DAZL protein expression was restricted to primary spermatocytes in regressed testis. These results show that DAZL and BOULE are expressed in spermatogonia at early stages in the Syrian hamster, then both proteins translocate to the cytoplasm when meiosis starts. In the adult regressed testis, the absence of DAZL in spermatogonia might be related to the decrease in germ cell number, suggesting that DAZ gene family expression is involved in changes in seminiferous epithelium during photoregression.

Analysis of DAZ gene expression in a partial AZFc deletion of the human Y chromosome

The azoospermia factor c (AZFc) region of the Y chromosome consists of repetitive amplicons and is therefore highly susceptible to structural rearrangements, such as deletions and duplications. The b2/b3 deletion is a partial AZFc deletion that is conventionally determined by the selective absence of sY1191 in sequence-tagged site polymerase chain reaction (PCR) and is generally believed to retain two of the four deleted in azoospermia (DAZ) genes on the Y chromosome. In the present study we determined the copy number and expression of DAZ genes in sY1191-negative individuals. Using a DAZ dosage PCR assay and Southern blot analysis we evaluated the expression of four DAZ genes in five of six sY1191-negative individuals. Furthermore, cloning and immunoblot analyses revealed that three or more DAZ genes are expressed in sY1191-negative testes with germ cells. The results indicate that the selective absence of sY1191 not only means b2/b3 deletion with two DAZ genes, but also includes another AZFc configuration with four DAZ genes. These results exemplify the prevalence of variations in the AZFc region of the human Y chromosome.

Molecular Characterization of Some Genetic Factors Controlling Spermatogenesis in Egyptian Patients with Male Infertility

ABSTRACT Men with severe infertility suffer a high risk of Y chromosome deletion, hence screening for these cases is recommended prior to treatment with assisted reproduction. Our study aimed to investigate and detect the azoospermia factor (AZF) region deletion, rearrangement and deleted azoospermia (DAZ) gene copy number variations in Egyptian azoospermic infertile men. This was tested on 54 Egyptian nonobstructive azoospermic (NOA) infertile men, with age ranged from 21 to 45 years (mean: 31.4 ± 6.1 years), by STS ± multiplex PCR using a set of 14 sequence tagged sites (STSs) from three different regions of the Y chromosome: AZFa, AZFb, AZFc and sY587/DraI PCRRFLP assay to determine DAZ copy number variations. The results revealed a significant prevalence of AZFc subtypes deletion and reduced DAZ gene dosage in Egyptian azoospermic cases affecting Y chromosome deletions. To our knowledge, this study is the first one to investigate AZFc subtypes deletion and DAZ gene dosage in Egyptian infertile men. We concluded that DAZ genes deletion is a risk factor for spermatogenic damage. How to cite this article Fayez AG, El-Sayed AS, El-Desouky MA, Zarouk WA, Kamel AK, Fahmi IM, El-Ruby MO. Molecular Characterization of Some Genetic Factors Controlling Spermatogenesis in Egyptian Patients with Male Infertility. Int J Infertility Fetal Med 2012;3(3):69-77.

The Caenorhabditis elegans Homologue of Deleted in Azoospermia Is Involved in the Sperm/Oocyte Switch

The Deleted in Azoospermia (DAZ) gene family encodes putative translational activators that are required for meiosis and other aspects of gametogenesis in animals. The single Caenorhabditis elegans homologue of DAZ, daz-1, is an essential factor for female meiosis. Here, we show that daz-1 is important for the switch from spermatogenesis to oogenesis (the sperm/oocyte switch), which is an essential step for the hermaphrodite germline to produce oocytes. RNA interference of the daz-1 orthologue in a related nematode, Caenorhabditis briggsae, resulted in a complete loss of the sperm/oocyte switch. The C. elegans hermaphrodite deficient in daz-1 also revealed a failure in the sperm/oocyte switch if the genetic background was conditional masculinization of germline. DAZ-1 could bind specifically to mRNAs encoding the FBF proteins, which are translational regulators for the sperm/oocyte switch and germ stem cell proliferation. Expression of the FBF proteins seemed to be lowered in the daz-1 mutant at the stage for the sperm/oocyte switch. Conversely, a mutation in gld-3, a gene that functionally counteracts FBF, could partially restore oogenesis in the daz-1 mutant. Together, we propose that daz-1 plays a role upstream of the pathway for germ cell sex determination.