Search

Purpose: The aim of this study was to identify the disease-causing mutations found in three infertile female patients who were diagnosed with abnormal zona pellucida (ZP) and empty follicle syndrome (EFS). Methods: We performed whole-exome sequencing and Sanger sequencing to identify and verify the disease-causing mutations. Additionally, we performed Western blotting and mini-gene splicing assay to assess the effects of the mutations. Results: We identified two novel compound heterozygous mutations in the ZP2 gene, a patient with an abnormal ZP carrying a novel compound heterozygous mutation (c.1695-2A>G and c.1831G>T, p.V611F) and a patient with EFS carrying a novel compound heterozygous mutation (c.1695-2A>G and c.1924 C>T, p.R642*). Furthermore, we identified a patient with typical abnormal ZP carrying a novel heterozygous mutation (c.400G>T, p.A134S) in the ZP3 gene. The splice site mutation (c.1695-2A>G) can cause abnormal pre-mRNA splicing that inserts an extra sequence of 61 bp in the mRNA of ZP2, and the missense mutation (c.1831G>T) can cause a decrease of ZP2 protein in HEK293 cells. Conclusion: We identified three novel mutations in the ZP2 gene and the ZP3 gene in three Chinese female patients with infertility. Our study expands the spectrum of ZP gene mutations and phenotypes and thus is beneficial in the genetic diagnosis of infertility in females. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to identify the genetic cause of two cases of Kufs disease in the same family. The two affected individuals exhibited different levels of severity under magnetic resonance imaging (MRI). Methods: Whole-exome sequencing was performed on affected individuals, and the candidate gene was confirmed by Sanger sequencing. Western blot analysis was used to evaluate the level of expression of CLN6 protein in 239T cells. Results: We identified a novel homozygous mutation of the CLN6 gene (c.14G>T, p.Arg5Leu) in a consanguineous Chinese family in which two people had Kufs disease. Both patients exhibited seizures and progressive psychomotor decline and mental deterioration without visual impairment. They had different ages of onset, although they carried the same missense mutation. The affected female showed a pronounced abnormal MRI signal in the bilateral hippocampus, while her younger brother only showed a very slight abnormal signal. Further study showed that this missense mutation could decrease the level of expression of CLN6 protein. Conclusions: A novel homozygous mutation of the CLN6 gene was identified, and patients with the same mutation showed different ages of onset and different levels of severity under MRI. Significance: Our study established that the same CLN6 mutation could produce different phenotypes in patients, and it has expanded the mutational and phenotypical spectrum of the CLN6 gene. [ABSTRACT FROM AUTHOR]

Purpose: To identify disease-causing genes involved in female infertility. Methods: Whole-exome sequencing and Sanger DNA sequencing were used to identify the mutations in disease-causing genes. We performed subcellular protein localization, western immunoblotting analysis, and co-immunoprecipitation analysis to evaluate the effects of the mutation. Results: We investigated 17 families with female infertility. Whole-exome and Sanger DNA sequencing were used to characterize the disease gene in the patients, and we identified a novel heterozygous mutation (p.Ser173Cys, c.518C > G) in the ZP3 gene in a patient with empty follicle syndrome. When we performed co-immunoprecipitation analysis, we found that the S173C mutation affected interactions between ZP3 and ZP2. Conclusions: We identified a novel mutation in the ZP3 gene in a Chinese family with female infertility. Our findings thus expand the mutational and phenotypical spectrum of the ZP3 gene, and they will be helpful in precisely diagnosing this aspect of female infertility. [ABSTRACT FROM AUTHOR]

Purpose: To identify the disease-causing gene in a family with female infertility and fertilization failure. Methods: Whole-exome sequencing and Sanger sequencing were used to identify the disease-causing gene in a female with infertility and fertilization failure. Subcellular localization and western blot analysis were used to check the effect of mutations. Results: We identified novel compound heterozygous mutations c.598C>T (p.Arg200Ter) and c.1319G>C (p.Trp440Ser) in WEE2 gene in a female with infertility and fertilization failure. The p.Arg200Ter mutant WEE2 gene produce truncated protein and mainly located in the nucleus, the same as the wild protein, while the p.Trp440Ser mutant WEE2 proteins are located in the nucleus and cytoplasm and the expression level of p.Trp440Ser mutant WEE2 protein is reduced significantly compared with that of wild-type WEE2. Conclusions: We discovered novel compound heterozygous mutations c.598C>T (p.Arg200Ter) and c.1319G>C (p.Trp440Ser) in WEE2 gene in a female whose oocytes could not form pronucleus after intracytoplasmic sperm injection (ICSI). Moreover, mutations in WEE2 gene affect the normal function of WEE2 proteins and cause fertilization failure. [ABSTRACT FROM AUTHOR]

Early embryonic arrest and fragmentation (EEAF) is a common cause of female infertility, but the genetic causes remain to be largely unknown. CIP2A encodes the cellular inhibitor of PP2A, playing a crucial role in mitosis and mouse oocyte meiosis. Exome sequencing and Sanger sequencing were performed to identify candidate causative genes in patients with EEAF. The pathogenicity of the CIP2A variant was assessed and confirmed in cultured cell lines and human oocytes through Western blotting, semi-quantitative RT-PCR, TUNEL staining, and fluorescence localization analysis. We identified CIP2A (c.1510C > T, p.L504F) as a novel disease-causing gene in human EEAF from a consanguineous family. L504 is highly conserved throughout evolution. The CIP2A variant (c.1510C > T, p.L504F) reduced the expression level of the mutant CIP2A protein, leading to the abnormal aggregation of mutant CIP2A protein and cell apoptosis. Abnormal aggregation of CIP2A protein and chromosomal dispersion occurred in the patient's oocytes and early embryos. We further replicated the patient phenotype by knockdown CIP2A in human oocytes. Additionally, CIP2A deficiency resulted in decreased levels of phosphorylated ERK1/2. We first found that the CIP2A loss-of-function variant associate with female infertility characterized by EEAF. Our findings suggest the uniqueness and importance of CIP2A gene in human oocyte and early embryo development. This work was supported by National Key Research and Development Program of China (2023YFC2706302), the National Natural Science Foundation of China (81000079 , 81170165 , and 81870959), the HUST Academic Frontier Youth Team (2016QYTD02), and the Key Research of Huazhong University of Science and Technology, Tongji Hospital (2022A20). [Display omitted] • Identification of CIP2A as a novel disease-causing gene for EEAF. • Demonstration that the CIP2A variant (c.1510C > T, p.L504F) is loss of function variant. • Distinct function of CIP2A in human oocytes compared to mouse oocytes. • Phenotype observed in the patient is replicated by CIP2A knockdown in human oocytes. • Apoptosis and reduced pERK1/2 levels caused by the CIP2A variant may contribute to EEAF. [ABSTRACT FROM AUTHOR]