Microdeletions In Azoospermia Factor Region Research Articles

Cytogenetic and Y-chromosome Micro-deletions Analysis of Infertile Indian Males with non-obstructive Azoospermia and Severe Oligozoospermia

This study aimed to determine the frequency and type of chromosome anomalies and Y-chromosome microdeletions in Indian infertile males by using non-obstructive azoospermia and severe oligozoospermia. The study included 168 Indian infertile males. G-banding cytogenetic analysis was performed on the peripheral blood lymphocytes of 91 men with non-obstructive azoospermia and 77 men with oligozoospermia. A molecular genetic analysis of Y-chromosome was also performed with multiplex polymerase chain reaction (M-PCR) amplification by using15 Y-specific sequence-tagged sites (STSs) of azoospermia factor (AZF) region to screen the microdeletions in AZFs region of Ychromosome. Out of 168 cases, 152 had normal karyotype 46,XY chromosomal constitution. Cytogenetic abnormalities were found in 13 (7.74%) infertile patients. The frequency of chromosomal anomalies for non-obstructive azoospermia 7 (4.16%) was slightly higher than severe oligozoospermia 6 (3.57%). Chromosomal variants werefound in 2.38% patients. The microdeletions of Y-chromosome were observed in 1.19% and 0.59% patients with non-obstructive azoospermia and severe oligozoospermia, respectively. Microdeletions of both AZFa and AZFc genes identified with normal karyotype. This study has provided information that genetic anomalies act as a risk factor for infertility. It is therefore suggested that genetic techniques should be used for diagnosis purpose to obtain the genetic data for possible genetic counseling/cure to minimize the risk of transmitted genetic anomalies.

INCIDENCE OF MICRODELETIONS IN THE AZF REGION OF THE Y CHROMOSOME IN SLOVAK PATIENTS WITH AZOOSPERMIA

The Y chromosome accumulates male-related genes including sex-determining region of Y-chromosome (SRY) and several spermatogenesis-related genes. The long arm contains azoospermia factor (AZF) region (including sub-regions AZFa, AZFb and AZFc). Microdeletions in this region are responsible for azoospermia and oligospermia and result in the male infertility. The aim of this study was to analyze incidence of microdeletions in the AZF region of Y chromosome in patients with azoospermia from Slovakia. Over the period from 2005 to 2009 a total of 239 men (mean age 31.74 years) were analyzed. The diagnosis of azoospermia was established on the basis of semen analysis. All patient samples were analyzed cytogenetically. Chromosomal analysis was performed on all patients on cultured lymphocytes from peripheral blood. For exact diagnosis of microdeletions in AZF region we used a PCR-method using a set of sequence-tagged sites from all AZF sub-regions (according to the recommendation by the European Academy of Andrology and the European Quality Monitoring Network Group). Among our 226 patients with azoospermia and with normal karyotype, 8 patients (mean age 30.6 years) had microdeletions in the AZF region of the Y chromosome (3.35%). Considering particular types of deletions we determined deletions in each region AZFa,b,c but also a complete deletion of the entire AZF region. The presence of microdeletion(s) in the AZFc region was the most frequent. In our study we found 12 patients (5%) with 47,XXY karyotype (Klinefelter syndrome), but these patients didn't have microdeletion of Y chromosomes. The study confirmed that percentage of microdeletions in the AZF region is low in Slovak azoospermic patients, but important from a prognostic view.

Molecular analysis of Y chromosome microdeletions in idiopathic cases of male infertility in Serbia

The aim of this study was to detect frequency of microdeletions of Y chromosome in idiopathic cases of male infertility in Serbian population. Patients were subjected to detailed clinical, endocrinological and cytogenetic examinations. Ninety patients with normal cytogenetic findings with azoospermia and severe oligozoospermia were included in the study. In these patients microdeletion analysis was performed by multiplex polymerase chain reaction (PCR) method on DNA extracted from peripheral blood. In each case 6 markers in azoospermia factor (AZF) regions were tested: sY84, sY86 (AZFa); sY127, sY134 (AZFb); sY254, sY255 (AZFc). Deletions on Y chromosome were detected in 14 of 90 cases (15.6%), 9 with azoospermia and 5 with severe oligozoospermia. Of total number of 17 deletions, 11 (64.7%) were detected in AZFc region, 3 (17.6%) in AZFa region and 3 (17.6%) in AZFb region. Microdeletions in AZF region of Y chromosome, especially AZFc microdeletions, represent common genetic cause of idiopathic azoospermia and severe oligozoospremia in Serbian infertile men. Therefore, testing for Y chromosome microdeletions should be considered as an important element in diagnosis and genetic counseling of infertile men in Serbia and decisions regarding the assisted reproduction should be made based on the presence and type of AZF microdeletions.