A novel missense mutation in QRICH2 causes male infertility due to multiple morphological abnormalities of the sperm flagella  

新的QRICH2错义突变引起精子鞭毛多发形态异常并致男性不育

作　　者：Yousaf Raza Huan Zhang Muhammad Zubair Ansar Hussain Nisar Ahmad Min Chen Gang Yang Musavir Abbas Tanveer Abbas Muhammad Shoaib Ghulam Mustafa Imtiaz Ali Meftah Uddin Suixing Fan Wasim Shah Qinghua Shi Yousaf Raza;张欢;Muhammad Zubair;Ansar Hussain;Nisar Ahmad;陈敏;杨刚;Musavir Abbas;Tanveer Abbas;Muhammad Shoaib;Ghulam Mustafa;Imtiaz Ali;Meftah Uddin;樊岁兴;Wasim Shah;史庆华(中国科学技术大学附属第一医院生殖与遗传中心,生命科学与医学部,生物医学与健康安徽省实验室,合肥综合性国家科学中心大健康研究院,安徽合肥230027)

机构地区：[1]Center for Reproduction and Genetics,The First Affiliated Hospital of USTC,Division of Life Sciences and Medicine,Biomedical Sciences and Health Laboratory of Anhui Province,Institute of Health and Medicine,Hefei Comprehensive National Science Center,University of Science and Technology of China,Hefei 230027,China

出　　处：《中国科学技术大学学报》2024年第9期24-32,68,69,共11页JUSTC

基　　金：supported by the National Key Research and Development Program of China(2021YFC2700202,2022YFA0806303 and 2022YFC2702601);the Global Select Project of the Institute of Health and Medicine,Hefei Comprehensive National Science Center(DJK-LX-2022010);USTC Research Funds of the Double First-Class Initiative(the Joint Fund for New Medicine of USTC)(YD9100002034);the Fundamental Research Funds for the Central Universities(WK9100000004).

摘　　要：Multiple morphological abnormalities of the sperm flagella(MMAF)are characterized by bent,irregular,short,coiled,and absent flagella.MMAF is caused by a variety of genes,some of which have been identified.However,the underlying genetic factors responsible for the majority of MMAF cases are still largely unknown.The glutamine-rich 2(QRICH2)gene plays an essential role in the development of sperm flagella by regulating the expression of essential sperm flagellar biogenesis-associated proteins,and genetic variants of QRICH2 have been identified as the primary cause of MMAF in humans and mice.Here,we recruited a Pakistani consanguineous family to identify the genetic variant causing infertility in patients with MMAF.Whole-exome sequencing and Sanger sequencing were conducted to identify potentially pathogenic variants causing MMAF in infertile patients.Hematoxylin and eosin(HE)staining was performed to analyze sperm morphology.Quantitative polymerase chain reaction,western blot,and immunofluorescence staining analyses were conducted to observe the expression of QRICH2 in spermatozoa.A novel homozygous missense variant(c.4618C>T)in QRICH2 was identified in the affected patients.Morphological analysis of spermatozoa revealed the MMAF phenotype in infertile patients.qPCR revealed a significant reduction in the level of sperm QRICH2 mRNA,and immunofluorescence staining revealed a lack of sperm QRICH2 expression.Additionally,patients harboring a homozygous QRICH2 mutation presented reduced expression of outer dense fiber 2(ODF2)in sperm,whereas sperm expression of A-kinase anchor protein 4(AKAP4)was normal.These findings expand our understanding of the genetic causes of MMAF-associated male infertility and emphasize the importance of genetic counseling.精子鞭毛多发形态异常(MMAF)表现为鞭毛弯曲、不规则、短小、卷曲和缺失。尽管部分引发MMAF的基因已经被发现,但大多数病例的致病基因仍不明确。富含谷氨酰蛋白2(QRICH2)基因通过调控精子鞭毛生成相关的关键蛋白表达,在精子鞭毛发育中起着重要作用,且QRICH2的遗传变异已被证实是人类和小鼠MMAF的主要原因。为探明MMAF的遗传基础,我们招募了来自巴基斯坦的近亲婚配致后代不育家系,以确定导致患者不育的遗传变异。通过全外显子组测序和Sanger测序分析,我们鉴定出了导致患者MMAF的候选致病变异。随后,使用苏木精和伊红(HE)染色分析精子形态,并通过定量聚合酶链反应(qPCR)、蛋白质印迹(Western blot)和免疫荧光染色分析精子中QRICH2的表达情况。在该家系的患者中,我们发现了QRICH2基因的一种新的纯合错义变异(c.4618C>T)。精子形态分析显示,患者表现出典型的MMAF表型。qPCR结果表明患者精子中QRICH2 mRNA水平显著降低,免疫荧光染色结果显示QRICH2蛋白表达缺失。此外,携带QRICH2纯合错义变异的患者精子中外周纤维2(ODF2)表达减少,而A-激酶锚定蛋白4(AKAP4)表达正常。这些发现扩展了我们对MMAF相关男性不育症遗传原因的理解,并强调了遗传咨询在此类疾病中的重要性。

关 键 词：male infertility MMAF ASTHENOZOOSPERMIA QRICH2 missense mutation 

分 类 号：R698+.2[医药卫生—泌尿科学]