Primary ciliary dyskinesia (PCD) is a clinically rare, genetically and phenotypically heterogeneous condition characterized by chronic respiratory tract infections, male infertility, tympanitis, and laterality abnormalities. PCD is typically resulted from variants in genes encoding assembly or structural proteins that are indispensable for the movement of motile cilia. Here, we identified a novel nonsense mutation, c.466G>T, in cilia- and flagella-associated protein 300 ( CFAP300 ) resulting in a stop codon (p.Glu156*) through whole-exome sequencing (WES). The proband had a PCD phenotype with laterality defects and immotile sperm flagella displaying a combined loss of the inner dynein arm (IDA) and outer dynein arm (ODA). Bioinformatic programs predicted that the mutation is deleterious. Successful pregnancy was achieved through intracytoplasmic sperm injection (ICSI). Our results expand the spectrum of CFAP300 variants in PCD and provide reproductive guidance for infertile couples suffering from PCD caused by them.
Adult ; Female ; Humans ; Male ; Pregnancy ; China ; Ciliary Motility Disorders/genetics* ; Codon, Nonsense ; East Asian People/genetics* ; Exome Sequencing ; Homozygote ; Infertility, Male/genetics* ; Kartagener Syndrome/genetics* ; Pedigree ; Sperm Injections, Intracytoplasmic ; Cytoskeletal Proteins/genetics*

Multiple morphological abnormalities of the flagella (MMAF) represent a severe form of sperm defects leading to asthenozoospermia and male infertility. In this study, we identified a novel homozygous splicing mutation (c.871-4 ACA>A) in the adenylate kinase 7 (AK7) gene by whole-exome sequencing in infertile individuals. Spermatozoa from affected individuals exhibited typical MMAF characteristics, including coiled, bent, short, absent, and irregular flagella. Transmission electron microscopy analysis showed disorganized axonemal structure and abnormal mitochondrial sheets in sperm flagella. Immunofluorescence staining confirmed the absence of AK7 protein from the patients' spermatozoa, validating the pathogenic nature of the mutation. This study provides direct evidence linking the AK7 gene to MMAF-associated asthenozoospermia in humans, expanding the mutational spectrum of AK7 and enhancing our understanding of the genetic basis of male infertility.
Humans ; Male ; Sperm Tail/ultrastructure* ; Homozygote ; Consanguinity ; Asthenozoospermia/pathology* ; Infertility, Male/genetics* ; Mutation ; Pakistan ; Adenylate Kinase/genetics* ; Adult ; Pedigree ; RNA Splicing ; Exome Sequencing ; Spermatozoa

Nonobstructive azoospermia (NOA), one of the most severe types of male infertility, etiology often remains unclear in most cases. Therefore, this study aimed to detect four biallelic detrimental variants (0.5%) in the minichromosome maintenance domain containing 2 ( MCMDC2 ) genes in 768 NOA patients by whole-exome sequencing (WES). Hematoxylin and eosin (H&E) demonstrated that MCMDC2 deleterious variants caused meiotic arrest in three patients (c.1360G>T, c.1956G>T, and c.685C>T) and hypospermatogenesis in one patient (c.94G>T), as further confirmed through immunofluorescence (IF) staining. The single-cell RNA sequencing data indicated that MCMDC2 was substantially expressed during spermatogenesis. The variants were confirmed as deleterious and responsible for patient infertility through bioinformatics and in vitro experimental analyses. The results revealed four MCMDC2 variants related to NOA, which contributes to the current perception of the function of MCMDC2 in male fertility and presents new perspectives on the genetic etiology of NOA.
Humans ; Male ; Azoospermia/genetics* ; Meiosis/genetics* ; Spermatogenesis/genetics* ; Adult ; Exome Sequencing ; Microtubule-Associated Proteins/genetics* ; Alleles ; Infertility, Male/genetics*

Multiple morphological abnormalities of sperm flagella (MMAF) is a severe form of asthenoteratozoospermia, characterized by morphological abnormalities and reduced motility of sperm, causing male infertility. Although approximately 60% of MMAF cases can be explained genetically, the etiology of the remaining cases is unclear. Here, we identified two novel compound heterozygous variants in the gene, dynein axonemal heavy chain 10 ( DNAH10 ), in three patients from two unrelated Pakistani families using whole-exome sequencing (WES), including one compound heterozygous mutation ( DNAH10 : c.9409C>A [p.P3137T]; c.12946G>C [p.D4316H]) in family 1 and another compound heterozygous mutation ( DNAH10 : c.8849G>A [p.G2950D]; c.11509C>T [p.R3687W]) in family 2. All the identified variants are absent or rare in public genome databases and are predicted to have deleterious effects according to multiple bioinformatic tools. Sanger sequencing revealed that these variants follow an autosomal recessive mode of inheritance. Hematoxylin and eosin (H&E) staining revealed MMAF, including sperm head abnormalities, in the patients. In addition, immunofluorescence staining revealed loss of DNAH10 protein signals along sperm flagella. These findings broaden the spectrum of DNAH10 variants and expand understanding of the genetic basis of male infertility associated with the MMAF phenotype.
Adult ; Humans ; Male ; Alleles ; Asthenozoospermia/pathology* ; Axonemal Dyneins/genetics* ; Dyneins/genetics* ; Exome Sequencing ; Infertility, Male/pathology* ; Mutation ; Pakistan ; Pedigree ; Sperm Tail/pathology*

Male factors contribute to 50% of infertility cases, with 20%-30% of cases being solely attributed to male infertility. Helicase for meiosis 1 ( HFM1 ) plays a crucial role in ensuring proper crossover formation and synapsis of homologous chromosomes during meiosis, an essential process in gametogenesis. HFM1 gene mutations are associated with male infertility, particularly in cases of non-obstructive azoospermia and severe oligozoospermia. However, the effects of intracytoplasmic sperm injection (ICSI) in HFM1 -related infertility cases remain inadequately explored. This study identified novel biallelic HFM1 variants through whole-exome sequencing (WES) in a Chinese patient with severe oligozoospermia, which was confirmed by Sanger sequencing. The pathogenicity of these variants was assessed using real-time quantitative polymerase chain reaction (RT-qPCR) and immunoblotting, which revealed a significant reduction in HFM1 mRNA and protein levels in spermatozoa compared to those in a healthy control. Transmission electron microscopy revealed morphological abnormalities in sperm cells, including defects in the head and flagellum. Despite these abnormalities, ICSI treatment resulted in a favorable fertility outcome for the patient, indicating that assisted reproductive techniques (ART) can be effective in managing HFM1 -related male infertility. These findings offer valuable insights into the management of such cases.
Humans ; Male ; Sperm Injections, Intracytoplasmic ; Oligospermia/therapy* ; Adult ; Spermatozoa/ultrastructure* ; Exome Sequencing ; Mutation

The syndrome of multiple morphological abnormalities of the sperm flagella (MMAF) is one of the most serious kinds of sperm defects, leading to asthenoteratozoospermia and male infertility. In this study, we use whole-exome sequencing to identify genetic factors that account for male infertility in a patient born from a consanguineous Pakistani couple. A homozygous frameshift mutation (c.1399_1402del; p.Gln468ArgfsTer2) in axonemal dynein light chain domain containing 1 ( AXDND1 ) was identified in the patient. Sanger sequencing data showed that the mutation was cosegregated recessively with male infertility in this family. Papanicolaou staining and scanning electron microscopy analysis of the sperm revealed severely abnormal flagellar morphology in the patient. Immunofluorescence and western blot showed undetectable AXDND1 expression in the sperm of the patient. Transmission electron microscopy analysis showed disorganized sperm axonemal structure in the patient, particularly missing the central pair of microtubules. Immunofluorescence staining showed the absence of sperm-associated antigen 6 (SPAG6) and dynein axonemal light intermediate chain 1 (DNALI1) signals in the sperm flagella of the patient. These findings indicate that AXDND1 is essential for the organization of flagellar axoneme and provide direct evidence that AXDND1 is a MMAF gene in humans, thus expanding the phenotypic spectrum of AXDND1 frameshift mutations.
Humans ; Male ; Sperm Tail/ultrastructure* ; Frameshift Mutation ; Infertility, Male/pathology* ; Pakistan ; Pedigree ; Consanguinity ; Axonemal Dyneins/genetics* ; Adult ; Spermatozoa ; Exome Sequencing

OBJECTIVE: To summarize the clinical characteristics, diagnosis, treatment and prognosis of dyskeratosis congenita (DC) in children, and to provide clinical experience for the diagnosis and treatment of DC. METHODS: The clinical data of children with dyskeratosis congenital admitted to Children's Hospital of Soochow University from May 2016 to May 2024 were retrospectively analyzed. Whole exome sequencing (WES) was performed, the patients were followed up and the related literature was reviewed. RESULTS: A total of 4 patients were enrolled. There were 1 male and 3 females. Two patients had spontaneous TINF2 mutation, one had TERT mutation, and one had DKC1 mutation. All of them had bone marrow hypoplasia. Two patients underwent allogeneic hematopoietic stem cell transplantation, and both had good engraftment. Anti-rejection drugs were stopped, and they survived more than 5 years of follow-up. One patient was followed up in outpatient department, and another patient was scheduled to undergo hematopoietic stem cell transplantation. CONCLUSION The onset of dyskeratosis congenita in children is insidious, so genetic diagnosis is particularly important. c.853_861delGTCATGCTG (p.285-287del) was a new mutation site of TINF2, which expanded the gene mutation spectrum of DC. Hematopoietic stem cell transplantation is an effective treatment for bone marrow failure, and the treatment of other organ complications depends on further genetic exploration.
Humans ; Dyskeratosis Congenita/therapy* ; Hematopoietic Stem Cell Transplantation ; Male ; Mutation ; Female ; Retrospective Studies ; Telomerase/genetics* ; Telomere-Binding Proteins/genetics* ; Child ; Cell Cycle Proteins/genetics* ; Nuclear Proteins/genetics* ; Child, Preschool ; Prognosis ; Exome Sequencing

OBJECTIVE: To analyze RELT gene mutation found in a pedigree with clinical features and inheritable pattern consistent with amelogenesis imperfecta (AI) in China, and to study the relationship between its genotype and phenotype. METHODS: Clinical and radiological features were recorded for the affected individuals. Peripheral venous blood samples of the patient and family members were collected for further study, and the genomic DNA was extracted to identify the pathogenic gene. Whole exome sequencing (WES) was performed to analyze the possible pathogenic genes, and Sanger sequencing was performed for validation. SIFT and PolyPhen-2 were used to predict and analyze the mutation effect. Comparison of RELT amino acids across different species were performed by using Uniprot website. In addition, the three-dimen-sional structures of the wild type and mutant proteins were predicted by Alphafold 2. RESULTS: The proband exhibited typical hypocalcified AI, with heavy wear, soft enamel, rough and discolored surface, and partial enamel loss, while his parents didn ' t have similar manifestations. WES and Sanger sequencing results indicated that the proband carries a homozygous frameshift mutation in RELT gene, NM_032871.3: c.1169_1170del, and both of his parents were carriers. This mutation was predicted to be pathogenic by SIFT and PolyPhen-2. Up to now, there were 11 mutation sites in RELT gene were reported to be associated with AI, and all of the patients exhibited with hypocalcified AI. Compared with the wild-type RELT protein, the mutant protein p. Pro390fs35 conformation terminated prematurely, affecting the normal function of the protein. CONCLUSION Through phenotype analysis, gene sequencing, and functional prediction of a Chinese family with typical amelogenesis imperfecta, this study found that RELT gene frameshift mutation can lead to protein dysfunction in AI patients. Further research will focus on the role and mechanism of RELT in enamel development at the molecular and animal levels, providing molecular biology evidence for the genetic counseling, prenatal diagnosis, and early prevention and treatment of AI.
Humans ; Amelogenesis Imperfecta/genetics* ; Frameshift Mutation ; Male ; Pedigree ; Female ; China ; Exome Sequencing ; Phenotype ; Adult

Autosomal dominant tubulointerstitial kidney disease (ADTKD) is a rare autosomal dominant hereditary disorder characterized by hyperuricemia, gout, impaired urinary concentration, and progressive renal failure. It is primarily caused by mutations in uromodulin (UMOD) gene. This study reports a family with ADTKD in which whole-exome sequencing and Sanger sequencing identified a missense mutation in the UMOD gene, c.761A>C (p.H254P), present in both the proband and affected relatives. According to American College of Medical Genetics and Genomics (ACMG) guidelines, this variant is classified as likely pathogenic. The mutation results in an amino acid substitution that may impair UMOD protein folding and intracellular trafficking. UMOD gene mutations are associated with ADTKD, and genetic testing plays a vital role in the early diagnosis and treatment of this condition, highlighting its importance in the diagnosis of rare kidney diseases.
Adult ; Humans ; Male ; Exome Sequencing ; Mutation ; Mutation, Missense ; Nephritis, Interstitial/genetics* ; Pedigree ; Uromodulin/genetics*

OBJECTIVES: Keratoconus (KC) is a progressive corneal ectasia disorder, arising from a myriad of causes including genetic predispositions, environmental factors, biomechanical influences, and inflammatory reactions. This study aims to identify potential pathogenetic gene mutations in patients with sporadic KC in the Han Chinese population. METHODS: Twenty-five patients with primary KC as well as 50 unrelated population-matched healthy controls, were included in this study to identify potential pathogenic gene mutations among sporadic KC patients in the Han Chinese population. Sanger sequencing and whole-exome sequencing (WES) were used to analyze mutations in the zinc finger protein 469 (ZNF469) gene. Bioinformatics analysis was conducted to explore the potential role of ZNF469 in KC pathogenesis. RESULTS: Five novel heterozygous missense variants were identified in KC patients. Among them, 2 compound heterozygous variants, c.8986G>C (p. E2996Q) with c.11765A>C (p. D3922A), and c.4423C>G (p. L1475V) with c.10633G>A (p. G3545R), were determined to be possible pathogenic factors for KC. CONCLUSIONS Mutations in the ZNF469 gene may contribute to the development of KC in the Han Chinese population. These mutation sites may provide valuable information for future genetic screening of KC patients and their families.
Adolescent ; Adult ; Female ; Humans ; Male ; Case-Control Studies ; China/ethnology* ; Exome Sequencing ; Genetic Predisposition to Disease ; Keratoconus/genetics* ; Mutation ; Mutation, Missense ; Transcription Factors/genetics* ; East Asian People/genetics*