目的:钙网蛋白3(CALR3)的双等位基因有害变异是否会导致受精失败(FF),
结论:在两名来自无关家庭的不育男性中发现了CALR3的双等位基因突变,并显示出与精子-透明带(ZP)结合失败相关的FF。
背景:在雄性小鼠中,据报道,Calr3基因敲除会导致男性不育和FF。然而,这背后的机制在人类中仍不清楚。
方法:在一家研究医院对患有原发性不育和精子头部畸形的汉族家庭样本进行测序研究,以确定潜在的遗传原因。
方法:通过计算机分析收集了两个以精子头部变形为特征的不育先证者的数据。使用光学和电子显微镜对先证者的精子细胞进行了表征,并通过功能测定来验证遗传因子的致病性。进行分区授精(SUZI)和IVF测定以确定FF的确切发病机理。给予ICSI以克服CALR3影响的男性不育。
结果:在两名来自无关家庭的不育男性中发现了CALR3的新型双等位基因有害突变。我们发现了一个纯合移码CALR3突变(M1:c.17_27del,p.V6Gfs*34)和一个复合杂合CALR3突变(M2:c.943A>G,p.N315D;M3:c.544T>C,p.Y182H).这些突变在普通人群中很少见,并在受影响的精子中引起顶体超微结构缺陷。此外,携带CALR3突变的患者精子不能与精子-ZP结合,或破坏配子融合或阻止卵母细胞活化.分子分析显示,CALR3对于ZP结合蛋白在人类中的成熟至关重要。值得注意的是,两名患者通过SUZI和ICSI尝试成功受精,以及突变精子中PLCζ的正常表达,表明ICSI是CALR3缺陷型FF的最佳治疗方法。
结论:结果基于两名患者的精子相关发现。需要进一步的研究以深入了解CALR3在人类睾丸中的发育阶段和功能。
结论:我们的发现强调了与精子缺陷相关的FF的潜在风险,为这些患者的个性化遗传咨询和临床治疗提供了有价值的参考。
背景:本研究得到了国家重点研发计划(2021YFC2700901)的资助,合肥综合性国家科学中心医疗-产业融合医疗装备创新研究平台项目(4801001202),国家自然科学基金(82201803,82371621,82271639),安徽省教育厅基金会(gxgwfx2022007),安徽省教委自然科学研究重点项目(2023AH053287),和安徽省临床医学研究转化项目(202204295107020037)。作者宣布没有竞争利益。
背景:不适用。
OBJECTIVE: Do biallelic deleterious variants of Calreticulin 3 (CALR3) cause fertilization failure (FF), resulting in male infertility in humans?
CONCLUSIONS: Biallelic mutations in CALR3 were identified in two infertile men from unrelated families and were shown to cause FF associated with failed sperm-zona pellucida (ZP) binding.
BACKGROUND: In male mice, the Calr3-knockout has been reported to cause male infertility and FF. However, the mechanism behind this remains unclear in humans.
METHODS: Sequencing studies were conducted in a research hospital on samples from Han Chinese families with primary infertility and sperm head deformations to identify the underlying genetic causes.
METHODS: Data from two infertile probands characterized by sperm head deformation were collected through in silico analysis. Sperm cells from the probands were characterized using light and electron microscopy and used to verify the pathogenicity of genetic factors through functional assays. Subzonal insemination (SUZI) and IVF assays were performed to determine the exact pathogenesis of FF. ICSI were administered to overcome CALR3-affected male infertility.
RESULTS: Novel biallelic deleterious mutations in CALR3 were identified in two infertile men from unrelated families. We found one homozygous frameshift CALR3 mutation (M1: c.17_27del, p.V6Gfs*34) and one compound heterozygous CALR3 mutation (M2: c.943A>G, p.N315D; M3: c.544T>C, p.Y182H). These mutations are rare in the general population and cause acrosomal ultrastructural defects in affected sperm. Furthermore, spermatozoa from patients harbouring the CALR3 mutations were unable to bind to the sperm-ZP or they disrupted gamete fusion or prevented oocyte activation. Molecular assays have revealed that CALR3 is crucial for the maturation of the ZP binding protein in humans. Notably, the successful fertilization via SUZI and ICSI attempts for two patients, as well as the normal expression of PLCζ in the mutant sperm, suggests that ICSI is an optimal treatment for CALR3-deficient FF.
CONCLUSIONS: The results are based on sperm-related findings from two patients. Further studies are required to gain insight into the developmental stage and function of CALR3 in human testis.
CONCLUSIONS: Our findings highlight the underlying risk of FF associated with sperm defects and provide a valuable reference for personalized genetic counselling and clinical treatment of these patients.
BACKGROUND: This study was supported by the National Key R&D Program of China (2021YFC2700901), Hefei Comprehensive National Science Center Medical-Industrial Integration Medical Equipment Innovation Research Platform Project (4801001202), the National Natural Science Foundation of China (82201803, 82371621, 82271639), Foundation of the Education Department of Anhui Province (gxgwfx2022007), Key Project of Natural Science Research of Anhui Educational Committee (2023AH053287), and the Clinical Medical Research Transformation Project of Anhui Province (202204295107020037). The authors declare no competing interests.
BACKGROUND: N/A.