Clinical feature of infertile men carrying balanced translocations involving chromosome 10: Case series and a review of the literature

Comprehensive analysis of chromosomal breakpoints and candidate genes associated with male infertility: insights from cytogenetic studies and expression analyses

The study aimed to investigate prevalent chromosomal breakpoints identified in balanced structural chromosomal anomalies and to pinpoint potential candidate genes linked with male infertility. This was acchieved through a comprehensive approach combining RNA-seq and microarray data analysis, enabling precise identification of candidate genes. The Cytogenetics data from 2,500 infertile males referred to Royan Research Institute between 2009 and 2022 were analyzed, with 391 cases meeting the inclusion criteria of balanced chromosomal rearrangement. Of these, 193 cases exhibited normal variations and were excluded from the analysis. By examining the breakpoints, potential candidate genes were suggested. Among the remaining 198 cases, reciprocal translocations were the most frequent anomaly (129 cases), followed by Robertsonian translocations (43 cases), inversions (34 cases), and insertions (3 cases).Some patients had more than one chromosomal abnormality. Chromosomal anomalies were most frequently observed in chromosomes 13 (21.1%), 14 (20.1%), and 1 (16.3%) with 13q12, 14q12, and 1p36.3 being the most prevalent breakpoints, respectively. Chromosome 1 contributed the most to reciprocal translocations (20.2%) and inversions (17.6%), while chromosome 14 was the most involved in the Robertsonian translocations (82.2%). The findings suggested that breakpoints at 1p36.3 and 14q12 might be associated with pregestational infertility, whereas breakpoints at 13q12 could be linked to both gestational and pregestational infertility. Several candidate genes located on common breakpoints were proposed as potentially involved in male infertility. Bioinformatics analyses utilizing three databases were conducted to examine the expression patterns of 78 candidate genes implicated in various causes of infertility.‏ In azoospermic individuals, significant differential expression was observed in 19 genes: 15 were downregulated (TSSK2, SPINK2, TSSK4, CDY1, CFAP70, BPY2, BTG4, FKBP6, PPP2R1B, SPECC1L, CENPJ, ‏SKA3, FGF9, NODAL, CLOCK), while four genes were upregulated ‏(‏HSPB1, MIF, PRF1, ENTPD6). In the case of Asthenozoospermia, seven genes showed significant upregulation (PRF1, DDX21, KIT, SRD5A3, MTCH1, DDX50, NODAL). Though RNA-seq data for Teratozoospermia were unavailable, microarray data revealed differential expression insix genes: three downregulated (BUB1, KLK4, PIWIL2) and three upregulated (AURKC, NPM2, RANBP2). These findings enhance our understanding of the molecular basis of male infertility and could provide valuable insights for future diagnostic and therapeutic strategies.

A retrospective analysis of 1600 infertility patients with azoospermia and severe oligozoospermia

OBJECTIVE

This study aimed to investigate the genetic etiology of male infertility patients.

METHOD

A total of 1600 male patients with infertility, including 1300 cases of azoospermia and 300 cases of severe oligozoospermia, underwent routine semen analysis, chromosomal karyotype analysis and sex hormone level testing. The Azoospermia factor (AZF) on the Y chromosome was detected using the multiple fluorescence quantitative PCR technique. Additionally, copy number variation (CNV) analysis was performed on patients with Sertoli-cell-only syndrome who had a normal karyotype and AZF.

RESULT

Chromosomal abnormalities were found in 334 cases (20.88 %) of the 1600 male infertility patients. The most common type of abnormality was sex chromosome abnormalities (18.94 %), with 47, XXY being the most frequent abnormal karyotype. The rates of chromosomal abnormalities were significantly different between the azoospermia group and the severe oligospermia group (23.69 % and 8.67 %, respectively; P<0.05). AZF microdeletions were detected in 155 cases (9.69 %), with various deletion types and AZFc region microdeletion being the most prevalent. The rates of AZF microdeletions were not significantly different between the azoospermia group and the severe oligospermia group (9.15 % and 12 %, respectively; P=0.133). In 92 patients with Sertoli-cell-only syndrome who had a normal karyotype and AZF, the detection rate of CNV was 16.3 %. Compared to the severe oligospermia group, the azoospermia group had higher levels of FSH and LH and lower levels of T and E2, and the differences were statistically significant (P<0.05).

CONCLUSIONS

Male infertility is a complex multifactorial disease, with chromosomal abnormalities and Y chromosome microdeletions being important genetic factors leading to the disease. Initial genetic testing of infertile men should include karyotyping and Y chromosome microdeletions. If necessary, CNV testing should be performed to establish a clinical diagnosis and provide individualized treatment for male infertility.

Recurrent miscarriage and male factor infertility: diagnostic and therapeutic implications. A narrative review

Introduction

Recurrent miscarriage is defined as 2 or more failed clinical pregnancies, typically known as repeated pregnancy loss, occurring before 20 gestational weeks, and further categorized into primary and secondary types. It represents a common and distressing condition to deal with in the field of reproductive medicine, usually affecting <5% of couples, with up to 50% of cases lacking a clearly defined aetiology. The epidemiology also varies depending on maternal age. Remarkably, the situation significantly afflicts expecting parents, whereas maternal factors, such as age and previous pregnancy loss rate, are commonly reported as risk factors. Although previously underestimated, existing evidence suggests the male factor is a possible cause of recurrent pregnancy loss.

Material and methods

A non-systematic literature review was conducted in the PubMed and Scopus databases for articles written in English investigating the possible association of the male factor in recurrent pregnancy loss. The eligible studies were synthesized in a narrative review format upon discussion and consensus among the authors after being previously independently assessed and selected.

Results

Lifestyle, obesity, genetic predisposition, chromosomal anomalies, endocrine dysfunction, anatomical abnormalities, immunological factors, infections, and oxidative stress can result in poor embryo development and recurrent miscarriage. Although professional organizations currently recognize male gender as a possible risk factor, specific recommendations on the diagnostic and therapeutic field are still lacking, and the condition necessitates a high level of suspicion and case-by-case management.

Conclusions

In this review, we delve deeper into the contribution of the male factor in the concept of recurrent miscarriage.

A Rare 46,X,t(Y;10)(q12;p14) Balanced Translocation in Non-Obstructive Azoospermic Patient with Elevated FSH and LH Levels

Structural chromosomal aberrations like translocations have been shown to cause spermatogenic failure. We report a rare 46,X,t(Y;10)(q12;p14) balanced translocation in an otherwise healthy non-obstructive azoospermic male with high follicle-stimulating hormone (26.65 IU/L) and high luteinizing hormone (13.58 IU/L). The patient was referred to us after clinical, hormonal, and histopathological investigations to identify chromosomal abnormalities by karyotyping and fluorescence in situ hybridization (FISH). Analysis of the banding pattern by karyotyping followed by FISH confirmed reciprocal translocation and identified the breakpoints at Yq heterochromatin (Yq12) and 10p14. Further molecular tests including AZF microdeletion assay were done, and the results, which showed no mutations in the analyzed genes, were provided by the referring doctor. Thus, our study points to the importance of conventional cytogenetic techniques in the preliminary evaluation of a genetic abnormality in cases of infertility and would help the patient make an informed decision before pursuing assisted reproductive technology.

Association between chromosome 22q11.2 translocation and male oligozoospermia

Chromosomal aberrations in peripheral blood are a major cause of reproductive disorders for the infertile couples. Reciprocal translocation is closely related to male infertility. The breakpoint of translocation may disrupt or dysregulate important genes related to spermatogenesis. The relationship between some breakpoints of chromosome and male infertility has been paid attention. Chromosome 22q11.2 translocation has not been reported with male infertility. The purpose of this study is to evaluate the relationship between chromosome 22q11.2 translocation and male infertility. All patients were collected from the second hospital of Jilin University. Semen parameters were detected using the computer-aided semen analysis system. Cytogenetic analysis was performed using standard operating procedure. Related genes on chromosomal breakpoints were searched using online mendelian inheritance in man (OMIM). The association between this breakpoint and spermatogenesis is also discussed. We report 6 cases of translocation in chromosome 22. Of 7 breakpoints involved in these translocations, the common feature is that they all included chromosome 22q11.2 translocation and presented with oligozoospermia. The analysis of breakpoint related genes showed testis-specific serine/threonine kinase 2 (TSSK2) gene is associated with human spermatogenesis impairment. Overall, these results suggest that the breakpoint involved in translocation deserves attention from physicians in genetic counseling. The breakpoint rearrangement has the possibility of disrupting spermatogenesis. The relationship between 22q11.2 breakpoint and male infertility deserves further study.

Case report: A non-obstructive azoospermia patient with heat shock factor-2 mutation

RATIONALE

Infertility is a common medical condition that affects nearly 15% of the world population. Non-obstructive azoospermia (NOA) is one of the most severe forms of male infertility. Some common structural variants, single nucleotide polymorphisms (SNPs), and genetic factors were reported to be associated with NOA. However, the underlying etiology and genetic mechanism(s) remain largely unclear. This report aimed to describe the associated mutation of the heat shock factor-2 (HSF2) gene in Chinese infertile men with NOA.

PATIENT CONCERNS

An apparently healthy 27-year-old man with a body mass index (BMI) of 23.31 kg/m had a 2-year history of primary infertility.

DIAGNOSES

The semen analysis of the patient showed a sperm concentration of 0/mL in 6.5 mL of semen. The patient was diagnosed with NOA by performing the comprehensive examinations including a detailed medical history, physical examination, chromosome analysis, Y-chromosome microdeletions, semen analysis, and hormone profiles.

INTERVENTIONS

The couple received artificial insemination by donor (AID) and a healthy girl was born after the embryo transfer.

OUTCOMES

We found a novel deletion-insertion variation c.326_326delinsGGAAGGTGAGCTATTGT in the exon 3 of the HSF2 gene by performing next-generation sequencing on him who was diagnosed NOA. We performed Sanger sequencing on this patient and confirmed the heterozygous missing insertion mutation in the patient. This is a novel mutation. The variant was heterozygous and categorized as pathogenic.

LESSONS

A novel deletion-insertion variation c.326_326delinsGGAAGGTGAGCTATTGT in the exon 3 of HSF2 gene HSF2 is predicted to be pathogenic and associated with the occurrence of NOA.

Coexistence of Fragile-X Syndrome, 8p23.1 Deletion, and Balanced Translocation t(7;10)(p10;q24) in a Single Family

Aims: Fragile-X syndrome (FXS) is the most common inherited form of intellectual disability; it is caused by an abnormal CGG-repeat expansion at the FMR1 gene. However, a few cases of girls with mutations in the FMR1 gene have been reported in the literature. In this study, we describe the clinical and genetic assessment of a family who exhibits the unusual coexistence of FXS, an 8p23.1 deletion, and balanced translocation t(7;10)(p10;q24) in multiple members, including a symptomatic girl with FXS. Materials and Methods: All of the family members underwent comprehensive clinical and neurological examinations. All members of the family were also molecularly diagnosed using a combination of fluorescent-polymerase chain reaction (PCR), Triplet Repeat Primed-PCR, capillary electrophoresis, and karyotyping. Results: We identified a male proband and a female patient that presented with the craniofacial characteristics of FXS, neuropsychomotor developmental delay, speech delay, intellectual deficit, and a positive molecular diagnosis of FXS. Interestingly, the female patient presented with a severe phenotype also associated with the presence of 8p23.1 deletion, while the proband patient presented a balanced translocation t(7;10)(p10;q24). Moreover, we detected multiple carriers of the FXS premutation in the family. Conclusions: To our knowledge, we describe for the first time the simultaneous occurrence of FXS and an 8p23.1 deletion and their possible synergistic effects on the phenotype of a female patient. Moreover, we describe the coexistence of FXS, an 8p23.1 deletion, and a balanced translocation t(7;10)(p10;q24) in the same family.

Expectant management and live birth outcomes for male balanced-translocation carriers: Two case reports and a literature review

RATIONALE

Couples with male balanced-translocation carriers may experience recurrent pregnancy loss (RPL). Although the expectant management of RPL has developed over many years, genetic counseling for RPL couples with male balanced-translocation carriers remains challenging. Here, we describe the expectant management of 2 male carriers of balanced translocations.

PATIENT CONCERNS

A 32-year-old and a 28-year-old man presented at the clinic with diagnoses of infertility following spontaneous abortions by their wives.

DIAGNOSIS

Both patients had normal semen diagnosed by routine semen analysis and underwent cytogenetic diagnoses.

INTERVENTIONS

Following genetic counseling and informed consent, both couples voluntarily chose expectant management with natural conception.

OUTCOMES

One couple experienced 2 natural pregnancies, the first of which ended in spontaneous abortion and the second produced a phenotypically normal infant. The other couple's first pregnancy resulted in a fetus with a balanced translocation confirmed by amniocentesis and cytogenetic analysis.

LESSONS

Expectant management with natural conception may be an alternative to genetic counseling in male balanced-translocation carriers with RPL, especially those who are reluctant to undergo preimplantation diagnosis.

Familial Dysalbuminemic Hyperthyroxinemia (FDH), Albumin Gene Variant (R218S), and Risk of Miscarriages in Offspring

BACKGROUND

Familial dysalbuminemic hyperthyroxinemia (FDH) is a rare autosomal dominant disorder whose clinical characteristics remain incompletely understood, we investigated the role of albumin gene mutation in relation to miscarriage rate in a large pedigree of FDH followed up for 4 years.

PATIENTS AND METHODS

The proband and extended family with unexplained miscarriage and hyperthyroxinemia were identified and genotypes in candidate genes and thyroid function tests (TFTs), including changes in TFTs during pregnancy were comprehensively assessed. We also evaluated the development and growth of children in this large FDH pedigree during four years follow-up.

RESULT

The R218S variant in the albumin gene was identified in the proband and her relatives with hyperthyroxinemia who were diagnosed as FDH. Among the family members who underwent TFTs, 11 of 17 (65%) had similar changes in levels of thyroid hormone, with an estimated FDH heritability of 86%. Moreover, 32% (95% CI 16-54%) of FDH women experienced miscarriages at a rate that was substantially higher than the spontaneous abortion rate reported in the general population in China (7-14%). During the follow-up, results revealed that free triiodothyronine (fT3) and thyroid stimulating hormone (TSH) levels were normal during the entire gestational period; comparing to their age-adjusted peers, both FDH affected and FDH unaffected children in this pedigree appeared to have lower body weight and height.

CONCLUSIONS

Albumin gene variant (R218S) not only causes FDH but also may be associated with a higher risk of miscarriages, although the growth of their children appears not to be affected by the age of 2 years.

Evaluation of chromosomal abnormalities and Y-chromosome microdeletions in 1696 Turkish cases with primary male infertility: A single-center study

OBJECTIVE

The aim of this study was to determine the frequencies of chromosomal abnormalities and Y-chromosome microdeletions in Turkish cases with primary male infertility in a single center.

MATERIAL AND METHODS

Chromosomal abnormalities and Y-chromosome microdeletions were investigated in 1696 cases with primary male infertility between 2012 and 2017. Karyotype analyzes and Y-chromosome microdeletions analyzes [azoospermia factor (AZF) regions] were performed in all cases by using standard cytogenetic methods and the multiplex polymerase chain reaction method, respectively.

RESULTS

Chromosomal abnormalities were found in 142 cases (8.4%; 142/1696). Y-chromosome microdeletions were detected in 46 cases (2.7%; 46/1696). Y-chromosome microdeletions in the AZFc region were found in 20 of 46 cases (43%).

CONCLUSION

This study is one of the few were a large number of cases was studied in Turkey. It indicates that cytogenetic and Y-chromosome microdeletion studies should be conducted in cases with primary male infertility prior to selecting assisted reproductive techniques.

Molecular cytogenetic characterization of small supernumerary marker 15 in infertile male: A case report

Small supernumerary marker chromosomes (sSMCs) are defined as structurally abnormal chromosomes that may be detected pre- or postnataly in patients with developmental and/or mental retardation or infertility. sSMC on chromosome 15 accounts for the highest proportion of all sSMCs and may be detected in subfertile individuals. The present study reports the case of a male patient with oligoasthenoteratozoospermia and an sSMC. The sSMC was identified and characterized according to G-banding analysis, chromosomal microarray analysis (CMA) and fluorescence in situ hybridization (FISH) analysis. Chromosomal karyotype analysis suggested that the patient presented with 47,XY,+mar. CMA was used to characterize the sSMC, which revealed a 0.44-Mb microduplication in 6q25.3q26. Subsequently, FISH using centromere-specific probes for chromosomes 13/21, 14/22 and 15 was applied to identify the origin of the sSMC, which was finally determined to be inverted duplicated(15)(q11.2). It was hypothesized that heterochromatin in the sSMC is responsible for the patient's fertility problem. The presence of heterochromatin may disrupt regular meiosis, thereby affecting normal spermatogenesis. Impaired spermatogenesis in infertile males with an sSMC derived from chromosome 15 was also reviewed by searching published literature and the sSMC database (http://ssmc-tl.com/sSMC.html). For patients with low sperm parameters and complete absence of spermatozoa in the ejaculate, including infertile males with an sSMC with spermatozoa, intracytoplasmic sperm injection is considered as an effective assisted reproductive technique. It may be concluded that molecular cytogenetic techniques are critical tools for delineating sSMCs in infertile males and may be beneficial in identifying sSMC carriers to ensure they receive clinical genetic counseling.

Ultrasonographic findings and prenatal diagnosis of Jacobsen syndrome: A case report and review of the literature

RATIONALE

Jacobsen syndrome (JBS) is a rare chromosomal disorder with variable phenotypic expressivity, which is usually diagnosed in infancy and childhood based on clinical examination and hematological and cytogenetic findings. Prenatal diagnosis and fetal ultrasonographic findings of JBS are rare.

PATIENT CONCERNS

A 38-year-old, gravida 3, para 1, pregnant woman underwent clinical ultrasound examination at 22 weeks of gestation.

DIAGNOSES

Ultrasonographic findings indicated an interventricular septal defect, the presence of septal blood flow, dilation of the left renal pelvis, and a single umbilical artery. Amniocentesis was performed to evaluate possible genetic causes of this diagnosis by cytogenetic and single nucleotide polymorphism (SNP) array analysis.

INTERVENTIONS

After genetic counseling and informed consent, the couple elected to terminate the pregnancy.

OUTCOMES

Karyotype analysis showed that the fetal karyotype was 46,XX,del(11)(q23). The SNP array revealed a 6.118 Mb duplication of 11q23.2q23.3 and a 15.03 Mb deletion of 11q23.3q25.

LESSONS

Ultrasonographic findings of fetal JBS, including an interventricular septal defect, dilation of the left renal pelvis, and a single umbilical artery, may be associated with a 15.03 Mb deletion of 11q23.3q25. Further cases correlating phenotype and genotype are required to predict the postnatal phenotype.

Chromosome 1q21 translocation and spermatogenesis failure: Two case reports and review of the literature

RATIONALE

For the carriers of chromosome reciprocal translocation, the reason why some are fertile and others are infertile remains unclear. Here, we describe 2 patients who are carriers of chromosome 1q21 translocation with azoospermia.

PATIENT CONCERNS

A 29-year-old male and a 33-year-old male presented at the clinic with a diagnosis of infertility.

DIAGNOSIS

Both patients with azoospermia were diagnosed with Routine semen analysis, cytogenetic diagnosis and detection of serum reproductive hormones. The karyotype results of 2 patients were 46,XY,t(1;17)(q21;q23) and 46,XY,t(1;10)(q21;p12), respectively.

INTERVENTIONS

After genetic counseling and informed consent, 1 patient (Case 2) chose microsopic testicular sperm extraction (micro-TESE).

OUTCOMES

After micro-TESE, no sperm was found for the patient. Finally, both patients chose clinical treatment through artificial insemination with donor sperm.

LESSONS

These outcomes suggest that breakpoint at 1q21 should be paid attention by physician in genetic counseling, may harbor some genes associated with spermatogenesis, and deserves further be studied on the function of related genes.

Clinical Features of Infertile Men Carrying a Chromosome 9 Translocation

Previous studies indicated that chromosome 9 translocations are involved in reduced male fertility and increased chance of miscarriage in the female partner. The aim of this study was to review the clinical features and genetic counselling requirements of infertile men carrying chromosome 9 translocations. This study analyzed fertile-age male carriers of chromosome 9 translocations, and included 12 clinical cases in our hospital. In our cases, three cases had oligozoospermia or severe oligozoospermia, while nine cases had normal semen. Of the latter nine cases, seven were associated with recurrent spontaneous abortions, and two produced a phenotypically normal child as confirmed by amniocentesis. Male chromosome 9 translocations and specific breakpoints from reported papers were searched using PubMed and CNKI database. A literature review identified 76 male patients who carried chromosome 9 translocations. Breakpoints at 9p12, 9p11, 9p10 and 9q34.1 were related to pregestational infertility, while breakpoints at 9p21, 9q10, 9q11, 9q13, 9q21.1, 9q22, 9q22.2, 9q22.3, 9q34, 9q34.2 and 9q34.3 exhibited gestational infertility. Chromosome translocations involving chromosome 9 lead to increased risk of miscarriage. Carriers of chromosome 9 translocations should be counselled to consider in vitro fertilization accompanied by preimplantation genetic diagnosis.

Association Between Polymorphisms in the Angiotensin-Converting Enzyme Gene and Non-Obstructive Azoospermia in the Chinese Han Population from Northeast China

Background

Genetic defects are commonly observed in infertile males, although the majority of cases remain idiopathic. In recent years, the relationship between single-nucleotide polymorphisms (SNPs) and male infertility has received increasing attention. The objective of this study was to explore the relationship between non-obstructive azoospermia (NOA) and single-nucleotide polymorphisms in the angiotensin-converting enzyme gene (ACE) using ligase detection reaction (LDR)–PCR.

Material/Methods

A retrospective study was performed and we screened 4 ACE SNPs (rs4316, rs4331, rs4343, and rs4362) in 121 NOA cases and 256 control subjects by LDR–PCR. The relationship between SNPs and NOA was analyzed.

Results

ACE SNPs were in Hardy-Weinberg equilibrium (P=0.089 for rs4331, P=0.089 for rs4343, P=0.089 for rs4316, and P=0.381 for rs4362). The allelic and genotypic frequencies of the 4 SNPs were not significantly different between cases and controls (P=0.123 for rs4331, P=0.123 for rs4343, P=0.123 for rs4316, and P=0.179 for rs4362). Haplotype analysis showed the existence of 3 haplotypes, TGAC, CAGT, and TGAT, which showed statistical significance of 0.889, 0.889, and 0.781, respectively, between cases and controls.

Conclusions

No significant association was found between ACE SNPs rs4316, rs4331, rs4343, or rs4362 and NOA in the Chinese Han population of Northeast China.

GATA4 screening in Iranian patients of various ethnicities affected with congenital heart disease: Co-occurrence of a novel de novo translocation (5;7) and a likely pathogenic heterozygous GATA4 mutation in a family with autosomal dominant congenital heart disease

BACKGROUND

Congenital heart disease (CHD) is the most common birth defect and a major health problem around the world. However, its exact etiology has remained unclear. Among various genetic contributing factors, GATA4 transcription factor plays a significant role in the CHD pathogenesis. In this study, GATA4 coding sequence was screened in Iranian patients of various ethnicities.

METHODS

Sixty six individuals with familial CHD referred to our center were recruited in this study. After receiving written informed consent from each individual or their parents, chromosomal analyses and GATA4 variant screening were performed. Pathogenicity of the suspected variants was evaluated using available online software tools: CADD, Mutation Taster, SIFT, and PolyPhen-2.

RESULTS

A total of twelve GATA4 variants were detected including five intronic, 2 exonic and 3 polymorphisms as well as 2 missense mutations, the c.1220C>A and c.1309G>A. Unlike the c.1220C>A, the likely pathogenic heterozygous c.1309G>A has not been previously associated with any phenotype. Here, we not only report, for the first time, a c.1309G>A-related CHD, but also report a novel de novo balanced translocation, 46,XY,t(5;7)(qter13;qter11), in the same patient which may have influenced the disease severity.

CONCLUSION

From screening GATA4 sequence in 66 Iranian patients of various ethnicities, we conclude that cytogenetic analysis and PCR-direct sequencing of different candidate genes may not be the best approach for genetic diagnosis in CHD. Applying novel approaches such as next-generation sequencing (NGS) may provide a better understating of genetic contributing factors in CHD patients for whom conventional methods could not reveal any genetic causative factor.