甘肃部分地区373例男性不育患者Y染色体AZF微缺失基因诊断的研究

目的研究甘肃地区男性不育患者Y染色体AZF区域微缺失的频率、分布情况方法采用多重PCR技术,对甘肃地区373例男性不育症患者进行Y染色体AZFa,AZFb,AZFc三个区域6个STS位点的微缺失检测。结果 373例男性不育患者中,42例发生了STS位点缺失,缺失率11.3%。其中无精子症因子AZFa(SY86,SY84)区未见缺失;AZFb(SY127,SY134)区缺失4例(9.52%);AZFc(SY254,SY255)区缺失32例(76.2%);AZFb+c区缺失5例(11.9%);AZFa+b+c缺失1例(2.38%)。结论甘肃部分地区AZF区域微缺失的频率、分布与国内其他报道一致,但是在本研究中未检测到AZFa区缺失患者。     

The common variant N372H in BRCA2 gene may be associated with idiopathic male infertility with azoospermia or severe oligozoospermia

OBJECTIVE: To explore the possible association between the common single nucleotide polymorphism N372H in human breast cancer susceptibility gene 2 (BRCA2) and the idiopathic male infertility with azoospermia or severe oligozoospermia. STUDY DESIGN: The study included 240 infertile patients with idiopathic azoospermia or severe oligozoospermia and 250 fathered controls. The allele and genotype frequencies of the polymorphism N372H in BRCA2 gene were investigated in both patients and controls using denaturing high performance liquid chromatography analysis (DHPLC). RESULTS: The frequency of allele H of the polymorphism N372H in patients was significantly higher than that of the controls (23.5% versus 17.6%, OR = 1.49, 95% CI 1.06-1.97, P = 0.02) and the subjects bearing rare allele H (NH + HH) significantly increased in patients compared with controls (41.7% versus 32.4%, 95% CI 1.03-2.15, P = 0.03). CONCLUSION: The results of this study suggested that the polymorphism N372H in BRCA2 gene may be associated with idiopathic male infertility with azoospermia or severe oligozoospermia.     

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.     

Genetic screening for chromosomal abnormalities and Y chromosome microdeletions in Chinese infertile men

Purposes

To investigate the frequency and type of both chromosomal abnormalities and Y chromosome microdeletions and analyze their association with defective spermatogenesis in Chinese infertile men.

Methods

This is a single center study. Karyotyping using G-banding and screening for Y chromosome microdeletion by multiplex polymerase chain reactio(PCR)were performed in 200 controls and 1,333 infertile men, including 945 patients with non-obstructive azoospermia and 388 patients with severe oligozoospermia.

Results

Out of 1,333 infertile patients, 154(11.55%) presented chromosomal abnormalities. Of these, 139 of 945 (14.71%) were from the azoospermic and 15 of 388 (3.87%) from the severe oligozoospermic patient groups. The incidence of sex chromosomal abnormalities in men with azoospermia was 11.53% compared with 1.03% in men with severe oligozoospermia (P < 0.01). Also 144 of 1,333(10.80%) patients presented Y chromosome microdeletions. The incidence of azoospermia factor(AZF) microdeletion was 11.75% and 8.51% in patients with azoospermia and severe oligozoospermia respectively. Deletion of AZFc was the most common and deletions in AZFa or AZFab or AZFabc were found in azoospermic men. In addition, 34 patients had chromosomal abnormalities among the 144 patients with Y chromosome microdeletions. No chromosomal abnormality and microdeletion in AZF region were detected in controls.

Conclusions

There was a high incidence (19.80%) of chromosomal abnormalities and Y chromosomal microdeletions in Chinese infertile males with azoospermia or severe oligozoospermia. These findings strongly suggest that genetic screening should be advised to infertile men before starting assisted reproductive treatments.     

Single-nucleotide polymorphisms in the human RAD21L gene may be a genetic risk factor for Japanese patients with azoospermia caused by meiotic arrest and Sertoli cell-only syndrome

Genetic mechanisms are implicated in some cases of male infertility. Recently, it was demonstrated that male mice lacking the gene for RAD21L exhibited azoospermia caused by meiotic arrest. Mouse RAD21L is a functionally relevant meiotic α-kleisin that is essential for male fertility. Therefore, we hypothesized that RAD21L mutations or polymorphisms may be associated with male infertility, especially azoospermia secondary to meiotic arrest. To determine if RAD21L defects are associated with azoospermia in groups of patients with meiotic arrest, we performed direct sequencing of the RAD21L coding regions in 38 Japanese patients with meiotic arrest and in 200 normal controls. Three coding single-nucleotide polymorphisms (SNP1–SNP3) were detected in the meiotic arrest patient group. Sertoli cell-only syndrome is considered a common cause of non-obstructive azoospermia. For comparison, the RAD21L coding regions in which SNP1–SNP3 were detected were sequenced in 140 patients with Sertoli cell-only syndrome. Statistical analyses were used to compare the two groups of patients with the control group. Genotype and allele frequencies of SNP2 and SNP3 were notably higher in the two patient groups compared with the control group (Bonferroni adjusted p value <0.016). These results suggest a critical role for RAD21L in human spermatogenesis.     

Gonadotropin-Releasing Hormone Test for Hypogonadic Men

Gonadotropin patterns before and after stimulation with gonadotropin-releasing hormone (GnRH) have been studied in 69 hypogonadic men of various types: patients with expansive hypothalamus-pituitary disorders before and after surgery, patients with hypogonadotropic hypogonadism, and patients with oligozoospermia or azoospermia who have primary partial or total testicular deficiency. Three characteristic gonadotropin patterns were found: (a) low basal values of LH and FSH with either absent or decreased and delayed responses; (b) normal basal values and pituitary responses above the normal range; or (c) high basal values and pituitary responses above the normal range. These gonadotropin patterns were correlated with disorders of the hypothalamus-pituitary-testis axis. The advantages and disadvantages of the GnRH test for the clinical evaluation of male hypogonadism are discussed.     

Y染色体微缺失影响男性不育的研究进展

近年的研究热点显示Y染色体遗传缺陷因素所致的男性生精障碍是不育的重要病因之一.人类基因组的成功测序认为Y染色体的同源性重组是微缺失的分子基础.现研究主要在AZF基因.现研究发现在Y染色体上的220个基因中,无精子症或少精子症患者位于Y染色体的长臂（Yq11）无精子因子（AZF）区的16个编码基因有缺失,是已知的导致男性不育的最主要的分子遗传病因.临床上常使用提纯周围血白细胞DNA加Y染色体特异性引物进行PCR扩增检测,为明确Y染色体基因的功能以及相互之间的联系及基因治疗奠定基础.     

性别相关的母血中游离胎儿DNA的Y染色体微缺失筛查的探索研究

目的：利用孕妇血浆中游离胎儿DNA进行Y染色体微缺失筛查,在孕早期排查出AZF缺失的男性胎儿。方法：留取16～20孕周进行唐氏筛查的孕妇血标本,提取出全血基因组DNA后利用AZF基因特异性引物进行多重PCR,跑胶检测实验结果。结果：妊娠女性胎儿的孕妇血浆DNA用AZF基因特异性引物没有扩增出特异性条带,而妊娠男性胎儿的孕妇血浆DNA用AZF基因特异性引物能够扩增出特异性条带。结论：通过提取孕妇血浆中的DNA能够检测到游离胎儿DNA,并能通过多重PCR鉴定出胎儿是否为AZF基因缺失,从而提前预测胎儿今后罹惠无精子症的风险。     

无精子症配偶宫颈粘液内的抗精子抗体分析

目的：研究无精子症男子配偶宫颈粘液内的抗精子抗体。方法：应用ELISA方法检测宫颈粘液中的抗精子抗体。结果：400例有精子男子配偶中92例为抗精子抗体阳性（23％），200例无精子症男子配偶中42例为抗精子抗体阳性（21％），两组比较差异不显著。结论：无精子症病人配偶中抗精子抗体的产生可能是精浆中的精子吸附抗原的结果。