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1.
EMBO Rep ; 24(2): e55778, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36440627

RESUMO

Following meiotic recombination, each pair of homologous chromosomes acquires at least one crossover, which ensures accurate chromosome segregation and allows reciprocal exchange of genetic information. Recombination failure often leads to meiotic arrest, impairing fertility, but the molecular basis of recombination remains elusive. Here, we report a homozygous M1AP splicing mutation (c.1074 + 2T > C) in patients with severe oligozoospermia owing to meiotic metaphase I arrest. The mutation abolishes M1AP foci on the chromosome axes, resulting in decreased recombination intermediates and crossovers in male mouse models. M1AP interacts with the mammalian ZZS (an acronym for yeast proteins Zip2-Zip4-Spo16) complex components, SHOC1, TEX11, and SPO16. M1AP localizes to chromosomal axes in a SPO16-dependent manner and colocalizes with TEX11. Ablation of M1AP does not alter SHOC1 localization but reduces the recruitment of TEX11 to recombination intermediates. M1AP shows cytoplasmic localization in fetal oocytes and is dispensable for fertility and crossover formation in female mice. Our study provides the first evidence that M1AP acts as a copartner of the ZZS complex to promote crossover formation and meiotic progression in males.


Assuntos
Meiose , Complexos Multiproteicos , Animais , Feminino , Masculino , Camundongos , Meiose/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ciclo Celular/metabolismo , Complexos Multiproteicos/metabolismo
2.
J Cell Mol Med ; 28(7): e18215, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38509755

RESUMO

Oligoasthenoteratospermia (OAT), characterized by abnormally low sperm count, poor sperm motility, and abnormally high number of deformed spermatozoa, is an important cause of male infertility. Its genetic basis in many affected individuals remains unknown. Here, we found that CCDC157 variants are associated with OAT. In two cohorts, a 21-bp (g.30768132_30768152del21) and/or 24-bp (g.30772543_30772566del24) deletion of CCDC157 were identified in five sporadic OAT patients, and 2 cases within one pedigree. In a mouse model, loss of Ccdc157 led to male sterility with OAT-like phenotypes. Electron microscopy revealed misstructured acrosome and abnormal head-tail coupling apparatus in the sperm of Ccdc157-null mice. Comparative transcriptome analysis showed that the Ccdc157 mutation alters the expressions of genes involved in cell migration/motility and Golgi components. Abnormal Golgi apparatus and decreased expressions of genes involved in acrosome formation and lipid metabolism were detected in Ccdc157-deprived mouse germ cells. Interestingly, we attempted to treat infertile patients and Ccdc157 mutant mice with a Chinese medicine, Huangjin Zanyu, which improved the fertility in one patient and most mice that carried the heterozygous mutation in CCDC157. Healthy offspring were produced. Our study reveals CCDC157 is essential for sperm maturation and may serve as a marker for diagnosis of OAT.


Assuntos
Astenozoospermia , Infertilidade Masculina , Proteínas de Membrana , Oligospermia , Animais , Humanos , Masculino , Camundongos , Astenozoospermia/genética , Astenozoospermia/metabolismo , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Camundongos Knockout , Mutação/genética , Oligospermia/genética , Oligospermia/metabolismo , Sêmen/metabolismo , Motilidade dos Espermatozoides/genética , Espermatozoides/metabolismo , Proteínas de Membrana/metabolismo
3.
Am J Hum Genet ; 108(2): 324-336, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33508233

RESUMO

Human infertility is a multifactorial disease that affects 8%-12% of reproductive-aged couples worldwide. However, the genetic causes of human infertility are still poorly understood. Synaptonemal complex (SC) is a conserved tripartite structure that holds homologous chromosomes together and plays an indispensable role in the meiotic progression. Here, we identified three homozygous mutations in the SC coding gene C14orf39/SIX6OS1 in infertile individuals from different ethnic populations by whole-exome sequencing (WES). These mutations include a frameshift mutation (c.204_205del [p.His68Glnfs∗2]) from a consanguineous Pakistani family with two males suffering from non-obstructive azoospermia (NOA) and one female diagnosed with premature ovarian insufficiency (POI) as well as a nonsense mutation (c.958G>T [p.Glu320∗]) and a splicing mutation (c.1180-3C>G) in two unrelated Chinese men (individual P3907 and individual P6032, respectively) with meiotic arrest. Mutations in C14orf39 resulted in truncated proteins that retained SYCE1 binding but exhibited impaired polycomplex formation between C14ORF39 and SYCE1. Further cytological analyses of meiosis in germ cells revealed that the affected familial males with the C14orf39 frameshift mutation displayed complete asynapsis between homologous chromosomes, while the affected Chinese men carrying the nonsense or splicing mutation showed incomplete synapsis. The phenotypes of NOA and POI in affected individuals were well recapitulated by Six6os1 mutant mice carrying an analogous mutation. Collectively, our findings in humans and mice highlight the conserved role of C14ORF39/SIX6OS1 in SC assembly and indicate that the homozygous mutations in C14orf39/SIX6OS1 described here are responsible for infertility of these affected individuals, thus expanding our understanding of the genetic basis of human infertility.


Assuntos
Azoospermia/genética , Mutação , Insuficiência Ovariana Primária/genética , Adulto , Azoospermia/fisiopatologia , Pareamento Cromossômico , Códon sem Sentido , Proteínas de Ligação a DNA/metabolismo , Feminino , Homozigoto , Humanos , Masculino , Meiose , Pessoa de Meia-Idade , Proteínas Nucleares/metabolismo , Linhagem , Insuficiência Ovariana Primária/fisiopatologia , Espermatócitos/metabolismo , Espermatócitos/fisiologia , Complexo Sinaptonêmico/genética , Complexo Sinaptonêmico/metabolismo , Sequenciamento Completo do Genoma
4.
Hum Mol Genet ; 30(21): 1977-1984, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34155512

RESUMO

Serine/threonine kinases domain-containing proteins are known to play important functions in sperm flagella and male fertility. However, the roles of these proteins in human reproduction remain poorly understood and whether their variants are associated with human asthenozoospermia have not been reported. Here, we recruited a Pakistani family having four infertile patients diagnosed with idiopathic asthenozoospermia without any ciliary-related symptoms. Whole-exome sequencing identified a novel homozygous frameshift mutation (c.1235del, p.T412Kfs*14) in serine/threonine kinase 33 (STK33), which displays a highly conserved and predominant expression in testis in humans. This variant led to a dramatic reduction of STK33 messenger RNA (mRNA) in the patients. Patients homozygous for the STK33 variant presented reduced sperm motility, frequent morphological abnormalities of sperm flagella and completely disorganized flagellar ultrastructures, which are typical for multiple morphological abnormalities of the flagella (MMAF) phenotypes. Overall, these findings present evidence establishing that STK33 is an MMAF-related gene and provide new insights for understanding the role of serine/threonine kinases domain-containing proteins in human male reproduction.


Assuntos
Astenozoospermia/diagnóstico , Astenozoospermia/genética , Mutação da Fase de Leitura , Predisposição Genética para Doença , Proteínas Serina-Treonina Quinases/genética , Cauda do Espermatozoide/metabolismo , Adulto , Estudos de Associação Genética , Homozigoto , Humanos , Masculino , Linhagem , Fenótipo , Análise do Sêmen , Cauda do Espermatozoide/patologia , Cauda do Espermatozoide/ultraestrutura
5.
Brief Bioinform ; 22(3)2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32393981

RESUMO

With the advances of next-generation sequencing technology, the field of disease research has been revolutionized. However, pinpointing the disease-causing variants from millions of revealed variants is still a tough task. Here, we have reviewed the existing linkage analysis tools and presented PedMiner, a web-based application designed to narrow down candidate variants from family based whole-exome sequencing (WES) data through linkage analysis. PedMiner integrates linkage analysis, variant annotation and prioritization in one automated pipeline. It provides graphical visualization of the linked regions along with comprehensive annotation of variants and genes within these linked regions. This efficient and comprehensive application will be helpful for the scientific community working on Mendelian inherited disorders using family based WES data.


Assuntos
Sequenciamento do Exoma/métodos , Família , Doenças Genéticas Inatas/genética , Ligação Genética , Algoritmos , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Masculino , Linhagem
6.
Clin Genet ; 104(5): 564-570, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37286336

RESUMO

Male infertility affects more than 20 million men worldwide and is a major public health concern. Male infertility has a strong genetic basis, particularly for those unexplained cases. Here, through genetic analysis of three Pakistani families having eight infertile men with normal parameters in routine semen analysis, we identified a novel ACTL7A variant (c.149_150del, p.E50Afs*6), recessively co-segregating with infertility in these three families. This variant leads to the loss of ACTL7A proteins in spermatozoa from patients. Transmission EM analyses revealed acrosome detachment from nuclei in 98.9% spermatozoa of patients. Interestingly, this ACTL7A variant was frequently detected in our sequenced Pakistani Pashtuns with a minor allele frequency of ~0.021 and all the carriers shared a common haplotype of about 240 kb flanking ACTL7A, indicating that it is likely originated from a single founder. Our findings reveal that a founder ACTL7A pathogenic variant confers a high genetic susceptibility for male infertility with normal routine semen parameters but acrosomal ultrastructural defects in Pakistani Pashtun descendants, and highlight that variants not rare should also be considered when trying to identify disease-causing variants in ethnic groups with the tradition of intra-ethnic marriages.


Assuntos
Acrossomo , Infertilidade Masculina , Humanos , Masculino , Infertilidade Masculina/genética , Paquistão , Sêmen , Espermatozoides/metabolismo
7.
Hum Reprod ; 37(7): 1664-1677, 2022 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-35526155

RESUMO

STUDY QUESTION: Do variants in helicase for meiosis 1 (HFM1) account for male infertility in humans? SUMMARY ANSWER: Biallelic variants in HFM1 cause human male infertility owing to non-obstructive azoospermia (NOA) with impaired crossover formation and meiotic metaphase I (MMI) arrest. WHAT IS KNOWN ALREADY: HFM1 encodes an evolutionarily conserved DNA helicase that is essential for crossover formation and completion of meiosis. The null mutants of Hfm1 or its ortholog in multiple organisms displayed spermatogenic arrest at the MMI owing to deficiencies in synapsis and severe defects in crossover formation. Although HFM1 variants were found in infertile men with azoospermia or oligozoospermia, the causal relationship has not yet been established with functional evidence. STUDY DESIGN, SIZE, DURATION: A Pakistani family, having two infertile brothers born to consanguineous parents, and three unrelated Chinese men diagnosed with NOA were recruited for pathogenic variants screening. PARTICIPANTS/MATERIALS, SETTING, METHODS: All the patients were diagnosed with idiopathic NOA and, for the Chinese patients, meiotic defects were confirmed by histological analyses and/or immunofluorescence staining on testicular sections. Exome sequencing and subsequent bioinformatic analyses were performed to screen for candidate pathogenic variants. The pathogenicity of identified variants was assessed and studied in vivo in mice carrying the equivalent mutations. MAIN RESULTS AND THE ROLE OF CHANCE: Six variants (homozygous or compound heterozygous) in HFM1 were identified in the three Chinese patients with NOA and two brothers with NOA from the Pakistani family. Testicular histological analysis revealed that spermatogenesis is arrested at MMI in patients carrying the variants. Mice modeling the HFM1 variants identified in patients recapitulated the meiotic defects of patients, confirming the pathogenicity of the identified variants. These Hfm1 variants led to various reductions of HFM1 foci on chromosome axes and resulted in varying degrees of synapsis and crossover formation defects in the mutant male mice. In addition, Hfm1 mutant female mice displayed infertility or subfertility with oogenesis variously affected. LIMITATIONS, REASONS FOR CAUTION: A limitation of the current study is the small sample size. Owing to the unavailability of fresh testicular samples, the defects of synapsis and crossover formation could not be detected in spermatocytes of patients. Owing to the unavailability of antibodies, we could not quantify the impact of these variants on HFM1 protein levels. WIDER IMPLICATIONS OF THE FINDINGS: Our findings provide direct clinical and in vivo functional evidence that HFM1 variants cause male infertility in humans and also suggest that HFM1 may regulate meiotic crossover formation in a dose-dependent manner. Noticeably, our findings from mouse models showed that HFM1 variants could impair spermatogenesis and oogenesis with a varying degree of severity and might also be compatible with the production of a few spermatozoa in men and subfertility in women, extending the phenotypic spectrum of patients with HFM1 variants. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Natural Science Foundation of China (31890780, 32070850, 32061143006, 32000587 and 31900398) and the Fundamental Research Funds for the Central Universities (YD2070002007 and YD2070002012). The authors declare no potential conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Azoospermia , Infertilidade Masculina , Animais , Azoospermia/patologia , DNA Helicases/genética , DNA Helicases/metabolismo , Feminino , Humanos , Infertilidade Masculina/diagnóstico , Masculino , Camundongos , Espermatogênese/genética , Espermatozoides/metabolismo , Testículo/metabolismo
8.
Int J Mol Sci ; 23(12)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35742973

RESUMO

Non-obstructive azoospermia (NOA), characterized by spermatogenesis failure and the absence of sperm in ejaculation, is the most severe form of male infertility. However, the etiology and pathology between meiosis-associated monogenic alterations and human NOA remain largely unknown. A homozygous MSH5 mutation (c.1126del) was identified from two idiopathic NOA patients in the consanguineous family. This mutation led to the degradation of MSH5 mRNA and abolished chromosome axial localization of MutSγ in spermatocytes from the affected males. Chromosomal spreading analysis of the patient's meiotic prophase I revealed that the meiosis progression was arrested at a zygotene-like stage with extensive failure of homologous synapsis and DSB repair. Therefore, our study demonstrates that the MSH5 c.1126del could cause meiotic recombination failure and lead to human infertility, improving the genetic diagnosis of NOA clinically. Furthermore, the study of human spermatocytes elucidates the meiosis defects caused by MSH5 variant, and reveals a conserved and indispensable role of MutSγ in human synapsis and meiotic recombination, which have not previously been well-described.


Assuntos
Azoospermia , Proteínas MutS/metabolismo , Azoospermia/genética , Proteínas de Ciclo Celular/metabolismo , Humanos , Masculino , Meiose/genética , Mutação , Sementes , Espermatócitos/metabolismo , Suporte de Carga
9.
Clin Genet ; 99(1): 176-186, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33070343

RESUMO

Multiple morphological abnormalities of the flagella (MMAF) is a genetically heterogeneous disorder leading to male infertility. Recent studies have revealed that DNAH17 variants are associated with MMAF, yet there is no functional evidence in support of their pathnogenicity. Here, we recruited two consanguineous families of Pakistani and Chinese origins, respectively, diagnosed with MMAF. Whole-exome sequencing identified novel homozygous DNAH17 variants, which led to loss of DNAH17 proteins, in the patients. Transmission electron microscope analyses revealed completely disorganized axonemal structure as the predominant anomaly and increased frequencies of missings of microtubule doublet(s) 4-7 in sperm flagella of patients. Similar to those found in patients, Dnah17-/- mice also displayed MMAF phenotype along with completely disorganized axonemal structures. Clusters of disorganized microtubules and outer dense fibers were observed in developing spermatids, indicating impaired sperm flagellar assembly. Besides, we also noticed many elongating spermatids with a deformed nuclear shape and abnormal step 16 spermatids that failed to spermiate, which subsequently underwent apoptosis in Dnah17-null mice. These findings present direct evidence establishing that DNAH17 is a MMAF-related gene in humans and mice, extend the clinical interpretations of DNAH17 variants, and highlight an essential and complex role of DNAH17 in spermatogenesis.


Assuntos
Anormalidades Múltiplas/genética , Dineínas do Axonema/genética , Infertilidade Masculina/genética , Espermatogênese/genética , Anormalidades Múltiplas/metabolismo , Anormalidades Múltiplas/patologia , Alelos , Animais , Astenozoospermia/genética , Astenozoospermia/patologia , Dineínas do Axonema/metabolismo , Axonema/genética , Axonema/patologia , Flagelos/genética , Flagelos/patologia , Homozigoto , Humanos , Infertilidade Masculina/patologia , Mutação com Perda de Função/genética , Masculino , Camundongos , Cauda do Espermatozoide/metabolismo , Cauda do Espermatozoide/patologia , Espermatozoides/metabolismo , Espermatozoides/patologia , Testículo/crescimento & desenvolvimento , Testículo/patologia , Sequenciamento do Exoma
10.
Hum Reprod ; 36(5): 1436-1445, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33713115

RESUMO

STUDY QUESTION: Are mutations in the zinc finger SWIM domain-containing protein 7 gene (ZSWIM7) associated with human male infertility? SUMMARY ANSWER: The homozygous frameshift mutation (c.231_232del) in ZSWIM7 causes decreased meiotic recombination, spermatogenesis arrest, and infertility in men. WHAT IS KNOWN ALREADY: ZSWIM7 is a SWIM domain-containing Shu2/SWS1 protein family member and a subunit of the Shu complex. Zswim7 knockout mice were infertile due to impaired meiotic recombination. However, so far there is no direct evidence that mutations of ZSWIM7 cause human infertility. STUDY DESIGN, SIZE, DURATION: Screening for mutations of ZSWIM7 was performed using in-house whole-exome sequencing data from 60 men with non-obstructive azoospermia (NOA). Mice with a corresponding Zswim7 mutation were generated for functional verification. PARTICIPANTS/MATERIALS, SETTING, METHODS: Sixty Chinese patients, who were from different regions of China, were enrolled. All the patients were diagnosed with NOA owing to spermatocyte maturation arrest based on histopathological analyses and/or immunostaining of spermatocyte chromosome spreads. ZSWIM7 mutations were screened from the whole-exome sequencing data of these patients, followed by functional verification in mice. MAIN RESULTS AND THE ROLE OF CHANCE: A homozygous frameshift mutation (c.231_232del) in ZSWIM7 was found in two out of the 60 unrelated NOA patients. Both patients displayed small testicular size and spermatocyte maturation arrest in testis histology. Spermatocyte chromosome spreads of one patient revealed meiotic maturation arrest in a pachytene-like stage, with incomplete synapsis and decreased meiotic recombination. Male mice carrying a homozygous mutation similar to that of our patients were generated and also displayed reduced recombination, meiotic arrest and azoospermia, paralleling the spermatogenesis defects in our patients. LIMITATIONS, REASONS FOR CAUTION: As Zswim7 is also essential for meiosis in female mice, future studies should evaluate the ZSWIM7 mutations more in depth and in larger cohorts of infertile patients, including males and females, to validate the findings. WIDER IMPLICATIONS OF THE FINDINGS: These findings provide direct clinical and functional evidence that the recurrent ZSWIM7 mutation (c.231_232del) causes decreased meiotic recombination and leads to male infertility, illustrating the genotype-phenotype correlations of meiotic recombination defects in humans. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Natural Science Foundation of China (31890780, 31630050, 32061143006, 82071709, and 31871514), the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB19000000), and the National Key Research and Developmental Program of China (2018YFC1003900 and 2019YFA0802600). TRIAL REGISTRATION NUMBER: Not applicable.


Assuntos
Azoospermia/genética , Proteínas de Ligação a DNA/genética , Animais , China , Feminino , Humanos , Masculino , Meiose , Camundongos , Mutação
11.
Hum Reprod ; 36(10): 2793-2804, 2021 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-34392356

RESUMO

STUDY QUESTION: Can whole-exome sequencing (WES) reveal pathogenic mutations in two consanguineous Pakistani families with infertile patients? SUMMARY ANSWER: A homozygous spermatogenesis associated 22 (SPATA22) frameshift mutation (c.203del), which disrupts the interaction with meiosis specific with OB-fold (MEIOB), and a MEIOB splicing mutation (c.683-1G>A) that led to loss of MEIOB protein cause familial infertility. WHAT IS KNOWN ALREADY: MEIOB and SPATA22, direct binding partners and functional collaborators, form a meiosis-specific heterodimer that regulates meiotic recombination. The protein stability and the axial localization of MEIOB and SPATA22 depend on each other. Meiob and Spata22 knockout mice have the same phenotypes: mutant spermatocytes can initiate meiotic recombination but are unable to complete DSB repair, leading to crossover formation failure, meiotic prophase arrest, and sterility. STUDY DESIGN, SIZE, DURATION: We performed WES for the patients and controls in two consanguineous Pakistani families to screen for mutations. The pathogenicity of the identified mutations was assessed by in vitro assay and mutant mouse model. PARTICIPANTS/MATERIALS, SETTING, METHODS: Two consanguineous Pakistani families with four patients (three men and one woman) suffering from primary infertility were recruited. SPATA22 and MEIOB mutations were screened from the WES data, followed by functional verification in cultured cells and mice. MAIN RESULTS AND THE ROLE OF CHANCE: A homozygous SPATA22 frameshift mutation (c.203del) was identified in a patient with non-obstructive azoospermia (NOA) from a consanguineous Pakistani family and a homozygous MEIOB splicing mutation (c.683-1G>A) was identified in two patients with NOA and one infertile woman from another consanguineous Pakistani family. The SPATA22 mutation destroyed the interaction with MEIOB. The MEIOB splicing mutation induced Exon 9 skipping, which causes a 32aa deletion in the oligonucleotide-binding domain without affecting the interaction between MEIOB and SPATA22. Furthermore, analyses of the Meiob mutant mice modelling the patients' mutation revealed that the MEIOB splicing mutation leads to loss of MEIOB proteins, abolished SPATA22 recruitment on chromosome axes, and meiotic arrest due to meiotic recombination failure. Thus, our study suggests that SPATA22 and MEIOB may both be causative genes for human infertility. LIMITATIONS, REASONS FOR CAUTION: As SPATA22 and MEIOB are interdependent and essential for meiotic recombination, screening for mutations of SPATA22 and MEIOB in both infertile men and women in larger cohorts is important to further reveal the role of the SPATA22 and MEIOB heterodimer in human fertility. WIDER IMPLICATIONS OF THE FINDINGS: These findings provide direct clinical and functional evidence that mutations in SPATA22 and MEIOB can cause meiotic recombination failure, supporting a role for these mutations in human infertility and their potential use as targets for genetic diagnosis of human infertility. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Key Research and Developmental Program of China (2018YFC1003900, 2018YFC1003700, and 2019YFA0802600), the National Natural Science Foundation of China (31890780, 31630050, 32061143006, 82071709, and 31871514), the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB19000000). The authors declare no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Azoospermia , Infertilidade/genética , Meiose , Animais , Proteínas de Ciclo Celular/genética , Consanguinidade , Proteínas de Ligação a DNA/genética , Humanos , Masculino , Camundongos , Camundongos Knockout , Mutação , Espermatogênese , Sequenciamento do Exoma
12.
Reprod Biomed Online ; 43(5): 913-919, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34493464

RESUMO

RESEARCH QUESTION: Male infertility is a global issue worldwide and multiple morphological abnormalities of the sperm flagella (MMAF) is one of the most severe forms of the qualitative sperm defects with a heterogeneous genetic cause that has not been completely understood. Can whole-exome sequencing (WES) reveal novel genetic causes contributing to MMAF in a consanguineous Pakistani family, comprising three infertile brothers? DESIGN: WES and bioinformatic analysis were conducted to screen potential pathogenic variants. The identified variant was validated by Sanger sequencing in all available family members Transmission electron microscopy analyses was carried out to examine the flagella ultrastructure of spermatozoa from patient. RESULTS: WES and Sanger sequencing identified a novel homozygous stop-gain mutation (ENST00000392644.4, c.182C>G, p.S61X) in ARMC2, which is expected to lead to loss of protein functions. Transmission electron microscopy analyses revealed that the flagellar ultrastructure of the patient's spermatozoa was disorganized along with a complete absence of central pair complex (CPC), suggesting that ARMC2 is involved in the assembly, stability of the axonemal complex, or both, particularly the CPC. CONCLUSION: We report that a familial stop-gain mutation in ARMC2 is associated with male infertility in humans caused by MMAF accompanied with loss of CPCs and axonemal disorganization. We provide genetic evidence that ARMC2 is essential for human spermatogenesis and its mutation may be pathogenic for MMAF. These findings will improve the knowledge about the genetic basis of MMAF and provide information for genetic counselling of this disease.


Assuntos
Proteínas do Citoesqueleto/genética , Cauda do Espermatozoide/patologia , Espermatozoides/anormalidades , Adulto , Consanguinidade , Proteínas do Citoesqueleto/fisiologia , Homozigoto , Humanos , Infertilidade Masculina/genética , Masculino , Microscopia Eletrônica de Transmissão , Mutação , Paquistão , Linhagem , Análise do Sêmen , Espermatogênese , Espermatozoides/ultraestrutura , Sequenciamento do Exoma
14.
Front Genet ; 15: 1429336, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39015774

RESUMO

Background: To investigate whether the novel mutation of PKHD1 could cause polycystic kidney disease by affecting splicing with a recessive inheritance pattern. Methods: A nonconsanguineous Chinese couple with two recurrent pregnancies showed fetal enlarged echogenic polycystic kidney and oligoamnios were recruited. Pedigree WES, minigene splicing assay experiment and following bioinformatics analysis were performed to verify the effects, and inheritance pattern of diseasing-causing mutations. Results: WES revealed that both fetuses were identified as carrying the same novel mutation c.3592_3628 + 45del, p.? and c.11207 T>C, p.(Ile3736Thr) in the PKHD1 gene (NM_138694.4), which inherited from the father and mother respectively. Both bioinformatic method prediction and minigene splicing assay experience results supported the mutation c.3592_3628 + 45del, p.? affects the splicing of the PKHD1 transcript, resulting in exon 31 skipping. Another missense mutation c.11207 T>C, p.(Ile3736Thr) has a low frequency in populations and is predicted to be deleterious by bioinformatic methods. Conclusion: These findings provide a direct clinical and functional evidence that the truncating mutations of the PKHD1 gene could lead to more severe phenotypes, and cause ARPKD as a homozygous or compound heterozygous pattern. Our study broadens the variant spectrum of the PKHD1 gene and provides a basis for genetic counseling and diagnosis of ARPKD.

15.
Asian J Androl ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38856307

RESUMO

ABSTRACT: Male infertility is a worldwide health issue, affecting 8%-12% of the global population. Oligoasthenoteratozoospermia (OAT) represents a severe type of male infertility, characterized by reduced sperm count and motility and an increased frequency of sperm with aberrant morphology. Using whole-exome sequencing, this study identified a novel missense mutation (c.848C>A, p.A283E) in the coiled-coil domain-containing 34 gene (CCDC34) in a consanguineous Pakistani family. This rare mutation was predicted to be deleterious and to affect the protein stability. Hematoxylin and eosin staining of spermatozoa from the patient with OAT revealed multiple morphological abnormalities of the flagella and transmission electron microscopy indicated axonemal ultrastructural defects with a lack of outer dynein arms. These findings indicated that CCDC34 plays a role in maintaining the axonemal ultrastructure and the assembly or stability of the outer dynein arms, thus expanding the phenotypic spectrum of CCDC34 missense mutations.

16.
Andrology ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39318356

RESUMO

BACKGROUND: HENMT1 encodes a small RNA methyltransferase that plays a crucial role in mouse spermatogenesis through the methylation of the 3' end of PIWI-interacting RNAs. OBJECTIVES: Our study aims to elucidate the relationship between HENMT1 and male infertility in humans. MATERIALS AND METHODS: A consanguineous family, having a single non-obstructive azoospermia patient was recruited for pathogenic variants screening. The research includes genetic analysis and experimental validation using mouse models. The patient was diagnosed with non-obstructive azoospermia. Whole-exome sequencing and subsequent bioinformatic analyses were performed to screen for candidate pathogenic variants. The pathogenicity of the identified variant was assessed and studied in vivo using a mouse model that mimicked the patient's mutation. RESULTS: Through whole-exome sequencing, we identified a homozygous nonsense variant (c.555G > A, p.Trp185*) in HENMT1 in the patient. The presence of the mutant HENMT1 mRNA was detected in the patient's blood, and the truncated HENMT1 protein was observed in transfected HEK293T cells. The mutant mice modeling this HENMT1 variant displayed an infertile phenotype similar to that of the patient, characterized by spermiogenesis arrest. Further analysis revealed a significant derepression of retrotransposon LINE1 in the testes of the Henmt1 mutant mice, and increased apoptosis of spermatids. DISCUSSION AND CONCLUSION: Our findings provide the evidence of pathogenicity of the identified HENMT1 variant, thus shedding light on the indispensable role of HENMT1 in human spermatogenesis.

17.
Zool Res ; 45(5): 1061-1072, 2024 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-39245650

RESUMO

The structural integrity of the sperm flagellum is essential for proper sperm function. Flagellar defects can result in male infertility, yet the precise mechanisms underlying this relationship are not fully understood. CCDC181, a coiled-coil domain-containing protein, is known to localize on sperm flagella and at the basal regions of motile cilia. Despite this knowledge, the specific functions of CCDC181 in flagellum biogenesis remain unclear. In this study, Ccdc181 knockout mice were generated. The absence of CCDC181 led to defective sperm head shaping and flagellum formation. Furthermore, the Ccdc181 knockout mice exhibited extremely low sperm counts, grossly aberrant sperm morphologies, markedly diminished sperm motility, and typical multiple morphological abnormalities of the flagella (MMAF). Additionally, an interaction between CCDC181 and the MMAF-related protein LRRC46 was identified, with CCDC181 regulating the localization of LRRC46 within sperm flagella. These findings suggest that CCDC181 plays a crucial role in both manchette formation and sperm flagellum biogenesis.


Assuntos
Camundongos Knockout , Proteínas dos Microtúbulos , Cauda do Espermatozoide , Animais , Masculino , Camundongos , Fertilidade/fisiologia , Flagelos/metabolismo , Flagelos/fisiologia , Motilidade dos Espermatozoides , Cauda do Espermatozoide/metabolismo , Cauda do Espermatozoide/fisiologia , Espermatozoides/fisiologia , Proteínas dos Microtúbulos/genética , Proteínas dos Microtúbulos/metabolismo
18.
Zool Res ; 45(5): 1073-1087, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39245651

RESUMO

Infertility represents a significant health concern, with sperm quantity and quality being crucial determinants of male fertility. Oligoasthenoteratozoospermia (OAT) is characterized by reduced sperm motility, lower sperm concentration, and morphological abnormalities in sperm heads and flagella. Although variants in several genes have been implicated in OAT, its genetic etiologies and pathogenetic mechanisms remain inadequately understood. In this study, we identified a homozygous nonsense mutation (c.916C>T, p.Arg306*) in the coiled-coil domain containing 146 ( CCDC146) gene in an infertile male patient with OAT. This mutation resulted in the production of a truncated CCDC146 protein (amino acids 1-305), retaining only two out of five coiled-coil domains. To validate the pathogenicity of the CCDC146 mutation, we generated a mouse model ( Ccdc146 mut/mut ) with a similar mutation to that of the patient. Consistently, the Ccdc146 mut/mut mice exhibited infertility, characterized by significantly reduced sperm counts, diminished motility, and multiple defects in sperm heads and flagella. Furthermore, the levels of axonemal proteins, including DNAH17, DNAH1, and SPAG6, were significantly reduced in the sperm of Ccdc146 mut/mut mice. Additionally, both human and mouse CCDC146 interacted with intraflagellar transport protein 20 (IFT20), but this interaction was lost in the mutated versions, leading to the degradation of IFT20. This study identified a novel deleterious homozygous nonsense mutation in CCDC146 that causes male infertility, potentially by disrupting axonemal protein transportation. These findings offer valuable insights for genetic counseling and understanding the mechanisms underlying CCDC146 mutant-associated infertility in human males.


Assuntos
Astenozoospermia , Proteínas Associadas aos Microtúbulos , Animais , Humanos , Masculino , Camundongos , Astenozoospermia/genética , Códon sem Sentido , Homozigoto , Infertilidade Masculina/genética , Mutação , Oligospermia/genética , Motilidade dos Espermatozoides/genética , Espermatozoides , Proteínas Associadas aos Microtúbulos/genética
19.
Asian J Androl ; 25(3): 350-355, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36308074

RESUMO

Multiple morphological abnormalities of the sperm flagella (MMAF) is a severe form of asthenozoospermia categorized by immotile spermatozoa with abnormal flagella in ejaculate. Whole-exome sequencing (WES) is used to detect pathogenic variants in patients with MMAF. In this study, a novel homozygous frameshift variant (c.6158_6159insT) in dynein axonemal heavy chain 8 (DNAH8) from two infertile brothers with MMAF in a consanguineous Pakistani family was identified by WES. Reverse transcription-polymerase chain reaction (RT-PCR) confirmed DNAH8 mRNA decay in these patients with the DNAH8 mutation. Hematoxylin-eosin staining and transmission electron microscopy revealed highly divergent morphology and ultrastructure of sperm flagella in these patients. Furthermore, an immunofluorescence assay showed the absence of DNAH8 and a reduction in its associated protein DNAH17 in the patients' spermatozoa. Collectively, our study expands the phenotypic spectrum of patients with DNAH8-related MMAF worldwide.


Assuntos
Infertilidade Masculina , Humanos , Masculino , Consanguinidade , Paquistão , Infertilidade Masculina/metabolismo , Sêmen/metabolismo , Cauda do Espermatozoide/metabolismo , Espermatozoides/metabolismo , Flagelos/genética , Flagelos/metabolismo , Flagelos/patologia , Mutação
20.
Front Endocrinol (Lausanne) ; 14: 1128362, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36864840

RESUMO

The meiosis-specific LINC complex, composed of the KASH5 and SUN1 proteins, tethers the moving chromosomes to the nuclear envelope to facilitate homolog pairing and is essential for gametogenesis. Here, we applied whole-exome sequencing for a consanguineous family with five siblings suffering from reproductive failure, and identified a homozygous frameshift mutation in KASH5 (c.1270_1273del, p.Arg424Thrfs*20). This mutation leads to the absence of KASH5 protein expression in testes and non-obstructive azoospermia (NOA) due to meiotic arrest before the pachytene stage in the affected brother. The four sisters displayed diminished ovarian reserve (DOR), with one sister never being pregnant but still having dominant follicle at 35 years old and three sisters suffering from at least 3 miscarriages occurring within the third month of gestation. The truncated KASH5 mutant protein, when expressed in cultured cells, displays a similar localization encircling the nucleus and a weakened interaction with SUN1, as compared with the full-length KASH5 proteins, which provides a potential explanation for the phenotypes in the affected females. This study reported sexual dimorphism for influence of the KASH5 mutation on human germ cell development, and extends the clinical manifestations associated with KASH5 mutations, providing genetic basis for the molecular diagnosis of NOA, DOR, and recurrent miscarriage.


Assuntos
Aborto Habitual , Azoospermia , Reserva Ovariana , Masculino , Feminino , Gravidez , Humanos , Adulto , Mutação da Fase de Leitura , Azoospermia/genética , Aborto Habitual/genética , Meiose , Proteínas de Ciclo Celular
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