Study of single nucleotide polymorphism (rs28368082) in SPO11 gene and its association with male infertility.

PURPOSE: The present study is a case-control analysis of a SNP (rs28368082) in exon 7 of the SPO11 gene and its possible association with male infertility in three provinces of Iran. We also searched for genetic differences among populations. METHODS: Using Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) analysis, we genotyped 113 infertile men and 50 fertile controls. Then, samples consisting SNP, as determined by PCR-RFLP, were genotyped by sequencing. The differences in genotype distributions between cases and fertile controls were examined using Chi-squared analysis. The genetic difference between individuals with mutated nucleotide was investigated by phylogenetic trees. Genetic difference among populations (provinces) was analyzed through ANOVA test, and homogeneity was investigated using STRUCTURE and K-means clustering analysis. RESULTS: According to the statistical analysis, the SNP was significantly associated with male infertility in all populations except oligozoospermic cases of the Center region. The phylogenetic trees showed partial genetic variation among the individuals, although ANOVA test showed no significant genetic difference between populations (provinces) for both azoospermic, and oligozoospermic cases. Eventually, we affirmed that individuals in the inclusive populations had genetic difference, but it was not statistically significant for dividing underlying populations to separate groups, so each population was homogenous. CONCLUSION: Our study indicates that the mentioned polymorphism in SPO11 gene may be linked to the susceptibility of azoospermia and oligozoospermia male infertility in three provinces of Iran. Further studies are required to support obtained results. It finally should be noted that the possible association between a particular SNP and a specific disease completely depends on the underlying population.

Screening of 'Y' chromosome microdeletions in Iranian infertile males.

BACKGROUND: It has been hypothesized that microdeletions of Yq may account for a significant proportion of men with infertility. Three nonoverlapping regions, referred to as "azoospermia factors" (AZFa, b, c from proximal to distal Yq) have been defined as spermatogenesis loci and deletions in these regions have been shown to be pathogenically involved in male infertility associated with azoospermia or severe oligospermia. AIMS: Evaluation the frequency of Y chromosome microdeletions in Iranian population. MATERIALS AND METHODS: Fifty infertile men were selected. Semen analysis was done and on the basis of the mean sperm count, all patients were categorized into azoospermia and oligozoospermia, groups. Blood samples were obtained for DNA extraction and chromosomal analysis. Genomic DNA was extracted from blood lymphocytes and amplified by sequence tagged sites-polymerase chain reaction (STS-PCR) method to determine the presence of microdeletions in AZF locus. A total of 34 STS primers including two controls were selected to identify microdeletions of Y chromosome on each subject. RESULTS AND CONCLUSION: 26/50 cases (52%) showed deletion of at least one of the STS Marker. Totally 41 microdeletions was observed. A total of 17 cases (34%) had deletion in one STS. Four oligospermia cases (8%) had deletion in 2 STS site. Three azoospermia cases (6%) had again deletion in 2 STS site, but in different STSs. One case had three deletions in three STS site and finally one individual had seven deletions in AZF locus. The overall frequency of Y chromosome microdeletions observed in the present study was found to be 26/50 (52%). Comparison of our data with the result of other investigators world wide shows that the incidence of Yq microdeletions in Iranian population is much higher than international frequency. Our data agree with other studies regarding microdeletions of AZFc, but for microdeletions of AZFa (14.6%) our results is much higher and differ significantly with many studies.

ABO blood group prevalence in spontaneously repeated abortion.

The relation of ABO blood groups to disease is well established. In 1943, Levine had identified ABO incompatibility as a cause of early abortions and stillbirths. From this time onwards numerous workers produced data suggesting, mainly on the grounds of a deficiency of A children, and an excess of abortions, in the families of O women married to A men, that the A fetuses produced by such mating were especially liable to be aborted. Seventy-nine couples from Pune city (India), suffering from repeated abortion have been investigated for the ABO blood groups system to find out the frequency of ABO blood group phenotypes and ABO incompatibility as a cause of abortion. In husband group maximum number of individuals had blood group A. In wife group, blood group B showed the highest number of individuals. In mixed group 154 patients have been tested and out of these, again blood group A, shows the highest number of individuals. Blood group "A" and "AB" was significantly higher in individual and mixed groups as compared with normal groups in this study. ABO blood group of husband/wife mating was also determined, the analysis of husband/wife joint "ABO" blood group distribution in these couples, shows an excess of joint "A/B" blood groups in couples as compared with expected proportions assuming random mating. This study came to a conclusion that there is a clear increase in number of individuals for blood group A and AB in-patients with repeated abortion, and this factor may need to pay more attention in future investigations. It is possible that incompatibility of the antigens present in red blood cell membrane of husband/wife may play some role in abortion.