High prevalence of genetic abnormalities in Middle Eastern patients with idiopathic non-obstructive azoospermia

Prevalence of Y-chromosomal microdeletions and karyotype abnormalities in a cohort of Lebanese infertile men

Background:

Male infertility is the main issue that accounts for 50% of infertility in couples. There are about 25% of men suffering from nonobstructive infertility with chromosomal abnormalities and/or microdeletions of the long arm of the Y-chromosome.

Materials and Methods:

A retrospective chart review was performed on 241 men who performed Y-chromosome microdeletions and karyotype testing.

Results:

Six patients had microdeletions. Three patients had AZFc microdeletion, of which one had both AZFc/d microdeletions. Three patients had AZFb/c microdeletion. There was no AZFa microdeletion. One out of the six patients had abnormal karyotype (mos, X[17]/46, XY[13]). Four patients were azoospermic, two had severe oligospermia, with sperm count <5 million/ml, and two patients had small size testicles on ultrasound. All were advised microsurgical testicular sperm extraction. Three were done, and one was successful resulting in sperm retrieval. The most common karyotype abnormalities were 47, XXY (Klinefelter syndrome) in 27% of cases.

Conclusion:

Laboratory genetic testing is advised for males with nonobstructive infertility. Any abnormal finding can yield substantial consequences to assisted reproductive techniques or fertility treatment. It can offer a stable diagnosis for those with infertility issues. It is important to conduct counseling and routine genetic testing before assisted reproductive techniques.

Mapping the Diverse Genetic Disorders and Rare Diseases Among the Syrian Population: Implications on Refugee Health and Health Services in Host Countries

The aim of this systematic review is to provide physicians and researchers with a comprehensive list of reported genetic disorders in patients of Syrian origin-those who have become part of the largest displaced population globally-and to highlight the need to consider migrant population-based risk for the development of genetic disease control and prevention programs. This review was performed based on the 2015 PRISMA and the international prospective register of systematic reviews. The present review reports on a total of 166 genetic disorders (only 128 reported on OMIM) identified in the Syrian population. Of these disorders, 27% are endocrine-, nutritional- and metabolic-related diseases. Second to metabolic disorders are congenital malformations, deformations and chromosomal abnormalities. Diseases of the blood and the blood-forming organs accounted for 13% of the total genetic disorders. The majority of the genetic disorders reported in Syrian patients followed an autosomal recessive mode of inheritance. These findings are a reflection of the high rates of consanguineous marriages that favor the increase in incidence of these diseases. From the diseases that followed an autosomal recessive mode of inheritance, 22% are reported to be only present in Syria and other regional countries. Twelve of these genetic diseases were identified to be strictly diagnosed in individuals of Syrian origin. The present systematic review highlights the need to develop programs that target genetic disorders affecting Syrian migrants in host countries. These programs would have potential financial and economic benefits, as well as a positive impact on the physical and mental health of members of the Syrian refugee community and those of their host societies. In turn, this would decrease the burden on the health systems in host countries.

Analysis of STAG3 variants in Chinese non-obstructive azoospermia patients with germ cell maturation arrest

STAG3 is essential for male meiosis and testis of male Stag3^-/- mice shows the histopathological type of germ cell maturation arrest (MA). Whether variants of the STAG3 gene exist in Chinese idiopathic non-obstructive azoospermia (NOA) patients needs to be determined. We recruited 58 Chinese NOA men with MA who underwent testis biopsy and 192 fertile men as the control group. The 34 exons of the STAG3 gene were amplified using polymerase chain reaction (PCR) and sequenced. We identified eight novel single nucleotide polymorphisms (SNPs), including two missense SNPs (c.433T > C in exon2 and c.553A > G in exon3), three synonymous SNPs (c.539G > A, c.569C > T in exon3, and c.1176C > G in exon8), and three SNPs in introns. The allele and genotype frequencies of the novel and other SNPs have no significant differences between two groups. Our results indicated that variants in the coding sequence of the STAG3 gene were uncommon in NOA patients with MA in Chinese population. Future studies in large cohorts of different ethnic populations will be needed to determine the association between the STAG3 gene and NOA.

CAG Repeats in the androgen receptor gene is associated with oligozoospermia and teratozoospermia in infertile men in Jordan

CAG trinucleotide repeats are coded for the polyglutamine tract in the N-terminal of the androgen receptor (AR) gene which varies in normal individuals from 6 to 36 residues. In this study, we inspected the impact of the CAG repeats on the spermatogenic defects by measuring the size of AR-CAG repeats length in a cohort of 260infertile and 169 fertile Jordanian men. The infertile group included three subgroups of a zoospermic, oligozoospermic and teratozoospermia men. The CAG allele size was determined by direct sequencing. The results showed a significant association between the length of the AR-CAG repeats and men's infertility (p = .001). In particular, the current cohort demonstrated a significant association between the AR-CAG length polymorphism and oligozoospermia (p < .001) and teratozoospermia (p < .001) but not azoospermia. According to distributions of allele frequency, the risk of oligozoospermia was 5.5-fold greater than normal when alleles frequency > 20 repeats, while the risk of teratozoospermia was > 10.6 folds greater than normal when allele frequency > 22 repeats. In conclusion, our results underscored that the long repeats of the AR-CAG polymorphism within the normal range might be associated with abnormal spermatogenesis such as teratozoospermia and oligozoospermia and contributing to infertility in Jordanian men.

Congenital anomalies prevalence in Addis Ababa and the Amhara region, Ethiopia: a descriptive cross-sectional study

Background

During the first three months of pregnancy, the developing embryo may be susceptible to external and internal factors, which may lead to structural and functional congenital anomalies. The main objective of this study was to determine the prevalence of congenital anomalies in Addis Ababa and the Amhara region, Ethiopia.

Methods

A descriptive cross-sectional study was conducted on children 0–17 years of age who visited the 16 selected hospitals in Addis Ababa and the Amhara Region between January 1 and July 5, 2015. The proportions of neonates, infants, and children with external and internal congenital anomalies whether the anomalies were major or minor were estimated.

Results

Out of 76,201 children, 1518 of whom 57.6% were male identified with congenital anomalies. The overall proportion of congenital anomaly was 1.99% (95% CI: 1.89–2.091) i.e., 199 per 10,000 children. The proportion of neural tube defects, orofacial clefts, masculo-skeletal system anomalies, syndrome disorders, and cardiovascular system problems were 40.3% 37.7–43, 23.3% 21.3–25.4, 23.1% 20.9–25.2, 8% 6.7–9.4, and 2.6% 1.8–3.4, with a 95% CI, respectively. The majority (72.5%) of the mothers were multigravidae; 38(2.5%) of the mothers and 32(2.1%) of the fathers had history of other children with congenital anomalies. Similarly, 20(1.3%) of the participant children’s mothers and 17(1.1%) of the fathers had familial history of congenital anomaly. Iron folate and multivitamin use by mothers during preconception and early pregnancy was found to be low.

Conclusion

Neural tube defects, orofacial clefts, and musculoskeletal anomalies were the observed prevalent problems. Maternal illness, viral infections, and malnutrition were seen in a significant number of the mothers. Iron folate/folic acid and multivitamin use by the mothers during and before pregnancy was very low.

Molecular analysis of CAG repeat length of the androgen receptor gene and Y chromosome microdeletions among Jordanian azoospermic infertile males

Assisted reproductive technology is a common procedure which helps millions of couples who suffer fertility problems worldwide every year. Screening for genetic abnormalities prior to such procedure is very important to prevent the transmission of harmful genetic mutations to future generations. Microdeletions within the azoospermia factor (AZF) region of the Y chromosome and the expansion of the CAG trinucleotides in the androgen receptor (AR) gene are among the susceptible causes of male infertility in different ethnic groups. Such association has never been studied in Jordan. In this study, we compared CAG repeat length between azoospermic infertile and normospermic fertile Jordanian males and we also screened the frequency of Y chromosome microdeletions in the same cohort. The study included 142 nonobstructive azoospermic cases and 145 normospermic controls. Results have shown that the median CAG repeat length in the azoospermic group is 19 ± 2 compared to 19 ± 1.5 (p = .6262) in the control group. Deletions within the Y chromosome AZF region were detected in 7 of 142 cases (4.93%) and no deletions were seen in the control group. The results of this study confirm the importance of the AZF region in normal spermatogenesis, whereas it shows no link between the length of CAG repeats in the AR gene and male azoospermia in Jordanian group examined.

Analysis of CDK2 mutations in Chinese men with non-obstructive azoospermia who underwent testis biopsy

To examine whether mutations of the CDK2 gene exist in Chinese men with non-obstructive azoospermia (NOA) with different histopathology, we recruited 175 Chinese men with idiopathic NOA who underwent testis biopsy, including hypospermatogenesis, germ cell maturation arrest and Sertoli cell only syndrome. Genomic DNA was extracted from peripheral blood samples. Subsequently, the seven exons of the CDK2 gene were amplified using polymerase chain reaction with specific primers, respectively. The polymerase chain reaction products were sequenced on an automated sequencer. We identified four known single nucleotide polymorphisms: c.324G>A in exon 1; c.363T>C in exon 2; c.*570G>A; and c.*1160G>C in the 3' UTR of the CDK2 gene. Comparison of the genotype and allele frequencies showed no significant differences between NOA cases and controls for the four single nucleotide polymorphisms. Furthermore, no significant differences were found between each pathological group and control group, respectively. The results indicate that mutations in the coding sequence of the CDK2 gene may not be responsible for idiopathic NOA in Chinese men. Future studies in large cohorts of different ethnic populations are warranted to establish whether associations exist between the CDK2 gene and NOA.

Mild androgen insensitivity syndrome (MAIS): the identification of c.1783C>T mutation in two unrelated infertile men

Two unrelated men complaining of primary male infertility presented to Orient Hospital in Damascus city. Physical examination showed moderate hypoandrogenic features. Both men were azoospermic. Hormone profiles revealed an elevation of follicle-stimulating hormone in one patient, but all the other hormones tested were within normal limits for both patients. Further genetic analyses, including karyotype and microdeletions in the AZF region of the Y chromosome, were normal in both patients. Mild androgen insensitivity syndrome was expected in the two patients. Sequencing analysis of the first exon in the androgen receptor (AR) gene have shown c.1783C>T mutation in the two patients with azoospermia. This paper sheds light on the need to screen for mutations in the AR gene, causing male infertility whenever mild hypoandrogenic features are present with unexplained male infertility.

Association and meta-analysis of HLA and non-obstructive azoospermia in the Han Chinese population

The exact aetiology and pathogenesis of most non-obstructive azoospermia (NOA) are still unknown. The previous two genomewide association studies (GWASs) have identified three different loci within the HLA region for NOA in the Han Chinese population, including rs3129878, rs498422 and rs7194. To further validate the risk of three GWAS-linked loci for NOA, we conducted a case-control study of these three risk loci in an independent Han Chinese male population, with 603 NOA patients and 610 controls. Furthermore, we also performed a meta-analysis of five studies on these three NOA-risk loci. The case-control study strongly suggested a significant association between loci rs3129878, rs498422 and rs7194 and NOA (P = 6.75 × 10^-21 (OR = 2.2586), P = 0.0060 (OR = 1.4013) and P = 0.0128 (OR = 1.2626) respectively). Our meta-analyses also supported the susceptibility of these three risk loci to NOA (P < 0.01). The risk variants within the HLA region potentially have a strong effect on males at risk of NOA, and may serve as diagnostic markers for male infertility. However, considering genetic difference between different populations, future validating studies in larger independent samples and animal experiments are suggested.

Karyotype analysis in large sample cases from Shenyang Women's and Children's hospital: a study of 16,294 male infertility patients

To explore that it is necessary to routinely detect chromosomes in infertile patients, we investigated peripheral blood lymphocyte karyotype in 16,294 male infertile patients in the north-east of China and analysed the incidence and type of chromosomal anomaly and polymorphism. G-banding karyotype analysis of peripheral blood lymphocytes was performed in 16,294 cases. Semen analysis was performed three times in all the men. PCR and FISH confirmed the presence of the SRY gene. The rate of chromosomal anomaly in the 16,294 male infertile patients was 4.15% (677/16,294). The rates of chromosomal anomaly were 0.24% in normal semen group, 12.6% in light oligoasthenospermia group, 4.7% in moderate-to-severe oligoasthenospermia group and 9.59% in azoospermia group. There are two male infertile patients with 45,X chromosome karyotype. One X male patient had confirmed the presence of the SRY gene and FISH analysis demonstrated its location on the p arm of chromosome 13. The other X male patient had not found SRY gene in its whole-genome DNA. Meanwhile, sperm motility is slightly oligo-asthenozoospermic at the age of 35-39 and nearly azoospermic at the age of 40-45. As the rates of chromosomal anomaly are 0.24% and 12.6% even in normal semen group and light oligoasthenospermia group, the rates of chromosomal polymorphism are 5.36% and 25.51% in normal semen group and light oligoasthenospermia group, respectively; it is necessary to explore peripheral blood lymphocyte karyotype in all infertile couples. We mentioned that Y, 1, 2, 9 and 12 chromosomes were quite important about male infertility. These findings demonstrate that autosomal retention of SRY can be submicroscopic and emphasise the importance of PCR and FISH in the genetic workup of the monosomic X male. At the same time, it suggested that male infertility might be related to meiotic disturbances with spermatogenetic arrest in Y-autosome translocations, which could result in infertility by reduction of sperm production. Last but not least, ageing is one of the factors that could reduce sperm motility and quality.

A study of aneuploidy and DNA fragmentation in spermatozoa of three men with sex chromosome mosaicism including a 45,X cell line

Meiotic segregation of mosaic males with a 45,X cell line has been little examined. In this study, we evaluated the risk of aneuploid gametes using fluorescence in situ hybridization (FISH) and DNA fragmentation in ejaculated spermatozoa of three men with sex chromosome mosaicism including a 45,X cell line. Triple- and dual-color FISH were performed. Sperm DNA fragmentation was detected using the TUNEL assay. A significantly increased frequency of XY disomic spermatozoa was observed for patients (P)1 and P2. A significant increase in diploidy and autosomal aneuploidy was found in P2 and P3, respectively. The rate of DNA fragmentation was not different from that observed in a control group. Data from the literature are scarce (only 3 cases reported), making comparison of the present data difficult, especially as the frequencies of the cell lines comprising the mosaicism differed between patients. Furthermore, the proportion of the different cell lines can differ from one tissue to another in the same patient. Whether the relative levels of the several cell lines present in the mosaicism can influence the rate of aneuploid spermatozoa remains unknown.