中华医学遗传学杂志最新文献

{"title":"[Clinical and genetic analysis of a child with Spastic paraplegia and psychomotor retardation with or without seizures due to compound heterozygous variants of the HACE1 gene].","authors":"Zhengfang Chen, Xiaoyan Xuan, Xiaoke Zhao","doi":"10.3760/cma.j.cn511374-20240508-00278","DOIUrl":"https://doi.org/10.3760/cma.j.cn511374-20240508-00278","url":null,"abstract":"<p><strong>Objective: </strong>To explore the genetic etiology of a child with Spastic paraplegia and psychomotor retardation with or without seizures (SPPRS).</p><p><strong>Methods: </strong>A child who was admitted to the Children's Hospital Affiliated to Nanjing Medical University in April 2022 for motor developmental delay, intellectual disability, and hypertonia was selected as the study subject. Relevant clinical data were retrospectively analyzed. Whole exome sequencing (WES) was carried out for the child and his parents. Candidate variants were searched in the Single Nucleotide Polymorphism Database (dbSNP) and Online Mendelian Inheritance in Man (OMIM) database. Pathogenicity of the variants was assessed based on guidelines from the American College of Medical Genetics and Genomics (ACMG). Using key words such as \"HACE1 gene\" \"Spastic paraplegia and psychomotor retardation with or without seizures\" and \"SPPRS\", previous reports on SPPRS patients due to HACE1 gene variants were retrieved from the CNKI, Wanfang Data Knowledge Service Platform, CQVIP, and PubMed databases, with the time set from January 1, 2000 to April 7, 2024. A mutation map for the HACE1 protein in the patients was created. This study was approved by the Ethics Committee of the Children's Hospital Affiliated to Nanjing Medical University (Ethics No. 202404008-1).</p><p><strong>Results: </strong>The clinical manifestations of the child had included motor developmental delay, intellectual disability and hypertonia. Magnetic resonance imaging revealed hypoplasia of posterior corpus callosum and splenium, with slight enlargement of lateral ventricles. WES revealed that the child has harbored compound heterozygous variants of the HACE1 gene, namely c.535(exon7)_c.538(exon7)delACAG (p.T179fs*5) and c.1678+2(IVS15)T>C, which were respectively inherited from his parents. Based on the guidelines from the ACMG, the variants were respectively rated as likely pathogenic (PVS1 + PM2_Supporting) and pathogenic (PVS1 + PM2_Supporting + PM3). Literature search has identified 8 papers, which reported 23 SPPRS cases due to HACE1 gene variants. All patients exhibited psychomotor developmental delay, among whom 18 HACE1 gene variants were identified.</p><p><strong>Conclusion: </strong>The c.535(exon7)_c.538(exon7)delACAG (p.T179fs*5) and c.1678+2(IVS15)T>C compound heterozygous variants of the HACE1 gene probably underlay the pathogenesis of SPPRS in this child. Above discovery has enriched the mutational and phenotypic spectrum of the HACE1 gene and provided a reference for clinical diagnosis and genetic counseling.</p>","PeriodicalId":39319,"journal":{"name":"中华医学遗传学杂志","volume":"42 2","pages":"156-161"},"PeriodicalIF":0.0,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144037379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Advancements in the application of RNA sequencing for genetic disorder diagnosis].","authors":"Jun An, Kexin Guo, Ping Hu","doi":"10.3760/cma.j.cn511374-20240821-00452","DOIUrl":"https://doi.org/10.3760/cma.j.cn511374-20240821-00452","url":null,"abstract":"<p><p>Next generation sequencing (NGS) technologies, including whole exome sequencing (WES) and whole genome sequencing (WGS), have greatly increased the diagnostic rates for genetic disorders. However, challenges still remain with the interpretation of variants of uncertain significance (VUS), variants in non-coding regions, and understanding of the effects of such variants on downstream genes. As a result, the diagnostic rates have typically ranged from 25% to 57%. RNA sequencing (RNA-seq) can complement DNA sequencing by revealing the functional consequences of genetic variants through the detection of aberrant gene expression, abnormal splicing events, allele-specific expression, and fusion gene expression. This has further increased the diagnostic rate of genetic disorders and enriched their therapeutic strategies. By broadening the scope of conventional genomic diagnostic methods, RNA-seq is poised to become a novel tool for the diagnosis of genetic disorders. This review has explored the methodologies and technical characteristics of RNA-seq by focusing on its recent advancement in clinical diagnosis, applications in undiagnosed genetic disorders, and the main challenges encountered.</p>","PeriodicalId":39319,"journal":{"name":"中华医学遗传学杂志","volume":"42 2","pages":"238-243"},"PeriodicalIF":0.0,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144020357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Carrier screening and prenatal diagnosis for Spinal muscular atrophy in 17 926 women of reproductive age in Chongqing].","authors":"Xia Chen, Yang Gao, Wenhong Chen, Xing Luo, Keya Tong","doi":"10.3760/cma.j.cn511374-20240808-00431","DOIUrl":"https://doi.org/10.3760/cma.j.cn511374-20240808-00431","url":null,"abstract":"<p><strong>Objective: </strong>To assess the carrier frequency of spinal muscular atrophy (SMA) in women of childbearing age in Chongqing and to evaluate prenatal diagnostic outcomes in high-risk couples.</p><p><strong>Methods: </strong>A total of 17 926 women of childbearing age attending Chongqing Health Center for Women and Children between May 2021 and November 2023 were enrolled, including 3 398 pre-pregnant women and 14 528 pregnant women, all of whom had no clinical phenotype or family history of SMA or related neuromuscular disorders. Real-time quantitative PCR (RT-qPCR) was used to determine the copy number variations in exons 7 and 8 (E7, E8) of the SMN1 gene. High-risk carriers were identified based on the genetic screening results. Multiplex ligation-dependent probe amplification (MLPA) was employed for prenatal diagnosis of fetuses from high-risk couples. This study was approved by the Medical Ethics Committee of Chongqing Health Center for Women and Children (Ethics No.2021-RGI-02).</p><p><strong>Results: </strong>Among the 17 926 women of childbearing age, 298 (1.66%) were identified as heterozygous carriers, including 278 (1.55%) with concurrent deletions of E7 and E8, and 20 (0.11%) with isolated deletions of E7. Seven high-risk couples were identified, six of whom were prenatal couples. Of the two fetuses from these high-risk pregnancies, both exhibited heterozygous deletions of E7 and E8 in the SMN1 gene, while four fetuses showed no abnormalities.</p><p><strong>Conclusion: </strong>This study provides a comprehensive assessment of the carrier frequency of SMA among women of childbearing age in Chongqing, offering valuable data for the primary and secondary prevention of SMA-related birth defects in the region.</p>","PeriodicalId":39319,"journal":{"name":"中华医学遗传学杂志","volume":"42 2","pages":"180-186"},"PeriodicalIF":0.0,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144048961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Advances in the study of signaling pathways in Global developmental delay /Intellectual disability combined with congenital craniofacial malformation].","authors":"Yunshu Jiang, Xiaonan Li","doi":"10.3760/cma.j.cn511374-20240924-00505","DOIUrl":"https://doi.org/10.3760/cma.j.cn511374-20240924-00505","url":null,"abstract":"<p><p>Global developmental delay (GDD) and intellectual disability (ID) refer to deficits in cognitive and adaptive functioning that arise during the developmental period. GDD/ID is often accompanied by complex developmental abnormalities, with congenital craniofacial malformations being among the most common, such as craniosynostosis, cleft lip and palate, and congenital tooth agenesis. However, the underlying mechanisms of GDD/ID associated with congenital craniofacial malformations remain unclear. With the increasing number of reported genetic syndromes, genetic factors are emerging as key contributors to the concurrent abnormalities in brain and craniofacial development. Studies have identified Wnt, SHH, FGF, and BMP as classical regulatory molecules in craniofacial development, and their roles have also been closely linked to various stages of brain development. This review focuses on the regulatory roles of Wnt, SHH, FGF, and BMP signaling pathways in brain and craniofacial development, as well as the pathogenic mechanisms underlying their association with GDD/ID and craniofacial malformations. The aim is to provide new insights into the etiology of GDD/ID combined with congenital craniofacial malformations.</p>","PeriodicalId":39319,"journal":{"name":"中华医学遗传学杂志","volume":"42 2","pages":"249-256"},"PeriodicalIF":0.0,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144033390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Clinical feature and genetic analysis of a child with X-linked Opitz G/BBB syndrome caused by nonsense variant in the MID1 gene mediated by mRNA degradation escape].","authors":"Yingyu Yan, Li He, Ying Yang, Duan Wang, Haiqing Zhang, Yanni Chen","doi":"10.3760/cma.j.cn511374-20240905-00470","DOIUrl":"https://doi.org/10.3760/cma.j.cn511374-20240905-00470","url":null,"abstract":"<p><strong>Objective: </strong>To explore the genotype-phenotype relationship in a child with Opitz G/BBB syndrome (OS) with mild clinical phenotype.</p><p><strong>Methods: </strong>A child with motor developmental delay as the initial symptom admitted to Xi'an Children's Hospital on June 10, 2021 was selected for this study. Clinical data were collected, and peripheral blood samples were obtained from the child and his mother. Whole exome sequencing (WES) was performed to identify genetic variant in the child. Candidate variant were verified by Sanger sequencing to assess inheritance patterns and pathogenicity. Real-time fluorescence quantitative PCR (RT-qPCR) and Western blot (WB) analyses were conducted to evaluate the effects of the variant on mRNA and protein expression, respectively, using recombinant expression plasmids generated in vitro. This study was approved by the Medical Ethics Committee of Xi'an Children's Hospital (Ethics No. 20240045).</p><p><strong>Results: </strong>The child, a 9-month-and-7-day-old boy, presented with a low nasal bridge, hypertelorism, and difficulty sitting independently. Echocardiography revealed an atrial septal defect. WES identified a homozygous variant in the MIDI gene, c.1483C>T (p.R495X), which was confirmed by Sanger sequencing and found to be inherited from the mother.Recombinant expression plasmids were successfully constructed. RT-qPCR analysis showed that the variant significantly reduced MIDI gene mRNA expression, while WB results indicated that the variant led to the production of a truncated protein.</p><p><strong>Conclusion: </strong>The mild clinical phenotype of OS in this child may be attributed to the mRNA degradation escape mechanism induced by the nonsense variant c.1483C>T (p.R495X) in the MIDI gene. These findings provide valuable diagnostic insights for this pedigree and contribute to the understanding of the genotype-phenotype correlation in OS.</p>","PeriodicalId":39319,"journal":{"name":"中华医学遗传学杂志","volume":"42 2","pages":"219-225"},"PeriodicalIF":0.0,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143990034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Genetic analysis of a fetus with Farber lipogranulomatosis caused by ASAH1 gene variant].","authors":"Yingwen Liu, Lulu Yan, Yuxin Zhang, Chunxiao Han, Haibo Li","doi":"10.3760/cma.j.cn511374-20240910-00482","DOIUrl":"10.3760/cma.j.cn511374-20240910-00482","url":null,"abstract":"<p><strong>Objective: </strong>To explore the clinical characteristics and gene variant of a fetus with Farber lipogranulomatosis caused by ASAH1 gene variant.</p><p><strong>Methods: </strong>A fetus with Farber lipogranulomatosis caused by ASAH1 gene variant diagnosed at Women and Children's Hospital of Ningbo University in August 2024 was selected as the subject. Clinical data and abortion tissue samples of the fetus and peripheral blood samples of its parents were collected for whole exome sequencing (WES). Sanger sequencing validation and bioinformatics analysis were performed on candidate variants. This study was approved by Women and Children's Hospital of Ningbo University (Ethics No. EC2020-048).</p><p><strong>Results: </strong>Generalized skin oedema, pericardial effusion, right pleural effusion and increased bowel echogenicity of the fetus were founded by prenatal ultrasound. WES revealed that the fetus has harbored a homozygous c.101C>A (p.Ser34Ter) variation in exon 2 of the ASAH1 gene. Sanger sequencing confirmed that both parents carry the heterozygous nonsense variation c.101C>A (p.Ser34Ter) in ASAH1 gene, which has not been included in databases such as HGMD, ClinVar, 1000 Genomes, ExAC, dbSNP, and gnomAD. Based on the Standards and Guidelines for the Interpretation of Sequence Variants of the American College of Medical Genetics and Genomics (ACMG), the variant was predicted to be pathogenic (PM2_Supporting+PVS1+PM3_Supporting). The AlphaFold3 model protein structure prediction reveals that the c.101C>A variant caused the premature appearance of a termination codon, resulting in only a small partial α-helix structure in the N-terminal of the encoded ASAH1 protein, with the complete loss of the α-helix structure in the core domain, which might lead to the loss of function of this protein.</p><p><strong>Conclusion: </strong>The c.101C>A (p.Ser34Ter) variant of the ASAH1 gene probably underlay the Farber lipogranulomatosis with hydrops fetalis in this fetus. The newly discovered c.101C>A (p.Ser34Ter) variant has enriched the mutational spectrum of Farber lipogranulomatosis.</p>","PeriodicalId":39319,"journal":{"name":"中华医学遗传学杂志","volume":"42 2","pages":"232-237"},"PeriodicalIF":0.0,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144023227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[The impact and clinical implication of variants in the start codon of HBA gene on the phenotype of thalassemia].","authors":"Bairu Lai, Yiyuan Ge, Xiaomin Ma, Guangkuan Zeng, Xiaohua Yu, Jianlian Liang, Yanbin Cao, Liye Yang","doi":"10.3760/cma.j.cn511374-20240829-00461","DOIUrl":"https://doi.org/10.3760/cma.j.cn511374-20240829-00461","url":null,"abstract":"<p><strong>Objective: </strong>To analyze the correlation between variants in the start codon of the α-globin gene and phenotypes of thalassemia, so as to provide a basis for the diagnosis and prevention of α-thalassemia.</p><p><strong>Methods: </strong>A retrospective study was conducted on 7 patients diagnosed by Yangjiang People's Hospital and Guangzhou Hybribio Co. Ltd., from June 2019 to October 2022. Routine blood tests and hemoglobin electrophoresis were carried out. Potential variants were identified through polymerase chain reaction (PCR) combined with Reverse dot blotting (RDB), Gap-PCR, and Sanger sequencing. This study has been approved by the Medical Ethics Committee of People's Hospital of Yangjiang (Ethics No: 20240001).</p><p><strong>Results: </strong>For the 7 patients, results of blood routine test of one case was unknown, and that of another was normal. The remaining 5 cases had presented with microcytic hypochromic anemia. The results of hemoglobin electrophoresis showed that one case had normal Hb A and slightly lower Hb A2, whilst another had significantly decreased Hb A and Hb A2, in addition with the appearance of a Hb H band. The content of Hb Bart's in four neonates was ≥ 0.4%. The remaining one case had no result. Genetic testing has identified 4 rare start codon mutations, namely HBA2: c.2delT, HBA2: c.1A>G, HBA2: c.1A>T, and HBA1: c.2T>C. Among these, Patient 1 had harbored compound heterozygous variants of HBA2: c.427T>C (Hb CS) and HBA2: c.2delT. Patient 4 had harbored compound heterozygous variants of HBA2: c.1A>G and Southeast Asian type deletion.</p><p><strong>Conclusion: </strong>Heterozygotes with HBA start codon variants usually present as silent or mild thalassemia, and the symptoms of anemia may deteriorate when combined with other α-thalassemia variant. The HBA2: c.1A>T start codon variant was unreported previously in China. The detection of start codon variants has helped to clarify the causes of anemia, genetic counseling, and guidance for reproduction.</p>","PeriodicalId":39319,"journal":{"name":"中华医学遗传学杂志","volume":"42 1","pages":"51-55"},"PeriodicalIF":0.0,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142956442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Antisense oligonucleotide as novel therapies for neurogenetic disorders].","authors":"Liyuan Fan","doi":"10.3760/cma.j.cn511374-20240821-00451","DOIUrl":"https://doi.org/10.3760/cma.j.cn511374-20240821-00451","url":null,"abstract":"<p><p>Antisense oligonucleotide (ASO) was discovered several decades ago and initially used only as a research tool in the laboratory. In recent years, several ASO therapeutics have been developed for neurological disorders. Some of these therapeutics, including eteplirsen, golodirsen, viltolarsen, nusinersen and inotersen, have been approved by the Food and Drug Administration (FDA) and begun to draw the public's attention as an effective therapeutic approach. These novel therapeutics have shown great performance, while many similar therapeutics are under investigation and in clinical trials. This n-of-1 precision medicine may start a new chapter in the paradigm of therapeutics. Clinicians, clinical geneticists, and genetic counselors may know about this novel therapy, but very few may understand the background in details. During genetic counseling, they have the responsibility to convey the effectiveness, side effects and cost of such therapies to patients and their families. As these target therapies will require precise genetic diagnosis before treatment, healthcare professionals and genetic counselors play a vital role in relating the patients to the corresponding ASO drugs. This review has elaborated the mechanism of ASO therapies, including basic rationales, modifications, side effects and delivery routes. It also systemically summarized the FDA-approved ASO therapeutics and their applications for various neurological disorders, and discussed the limitations and challenges the real-world market may face and issues genetic counselor should take into consideration in the near future.</p>","PeriodicalId":39319,"journal":{"name":"中华医学遗传学杂志","volume":"42 1","pages":"102-113"},"PeriodicalIF":0.0,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142956360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Genetic analysis of a child with Leukoencephalopathy with ataxia caused by a homozygous variant of CLCN2 gene and a literature review].","authors":"Zhen Zhou, Sai Yang, Zeshu Ning, Bo Chen, Miao Wang, Liwen Wu","doi":"10.3760/cma.j.cn511374-20241014-00533","DOIUrl":"10.3760/cma.j.cn511374-20241014-00533","url":null,"abstract":"<p><strong>Objective: </strong>To explore the clinical manifestations and genetic characteristics of a child with Leukoencephalopathy with ataxia (LKPAT) caused by a CLCN2 gene variant.</p><p><strong>Methods: </strong>A retrospective analysis was conducted on the clinical data of a child admitted to Hunan Children's Hospital in June 2024 due to \"intermittent convulsions for 13 days\". Peripheral blood samples were collected from the child and his parents for whole exome sequencing, followed by Sanger sequencing validation and pathogenicity analysis of candidate variants. Literature searches were performed using the keywords \"CLCN2 gene\" \"chloride channel-2\" \"leukoencephalopathy with ataxia/LKPAT\" \"leukoencephalopathy\" in both Chinese and English on CNKI, Wanfang, and PubMed databases. The search time was set from the establishment of the databases to July 31, 2024. Childhood-onset LKPAT literature was screened and analyzed. This study was approved by the Medical Ethics Committee of Hunan Children's Hospital (Ethics No. HCHLL-2024-351).</p><p><strong>Results: </strong>The child was a 7-month-and-26-day-old male infant born to consanguineous parents, presenting with epileptic seizures and borderline development. Cranial MRI revealed symmetrical long T₂ signal shadows in the posterior limb of the internal capsule, cerebral peduncle, pons, and middle peduncle of the cerebellum. Video electroencephalogram (EEG) showed an abnormal childhood EEG with one focal seizure. Whole exome sequencing revealed a homozygous c.2201dup (p.Glu735Ter) variant in the CLCN2 gene of the child. Sanger sequencing confirmed that the variant was inherited from both parents. According to the guidelines of the American College of Medical Genetics and Genomics (ACMG) and the Association for Molecular Pathology (AMP), this variant was classified as pathogenic (PVS1+PM3_Supporting+PM2_Supporting). A total of 8 relevant literature were retrieved, together with the present case, 16 childhood-onset LKPAT patients were cumulatively reported, which consisted of 9 males and 7 females. Twelve CLCN2 gene variants were involved, including 2 nonsense variants, 3 missense variants, 7 frameshifting variants, 2 c.61dup variants, and 5 c.1709G>A variants. The initial symptoms of the 16 patients included headache, ataxia, epileptic seizures, spasticity, developmental delay, lower back pain, hearing impairment, and intention tremor. Three patients had onset of the disease before the age of one, of which 2 had epileptic seizures as the initial symptom.</p><p><strong>Conclusion: </strong>The homozygous variant CLCN2: c.2201dup (p.Glu735Ter) is considered the pathogenic cause of LKPAT in this child, marking the first childhood-onset case reported in China. Genetic testing has facilitated the diagnosis of childhood-onset LKPAT and expanded the spectrum of CLCN2 gene mutations.</p>","PeriodicalId":39319,"journal":{"name":"中华医学遗传学杂志","volume":"42 1","pages":"82-88"},"PeriodicalIF":0.0,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142956271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Genetic analysis of a Chinese pedigree affected with Charcot-Marie-Tooth type 2A2A due to a missense variant of MFN2 gene].","authors":"Yu Han, Jie Liang, Jiebin Wu, Jingfang Zhai","doi":"10.3760/cma.j.cn511374-20240905-00471","DOIUrl":"10.3760/cma.j.cn511374-20240905-00471","url":null,"abstract":"<p><strong>Objective: </strong>To explore the genotype-phenotype correlation in a Charcot-Marie-Tooth type 2A2A (CMT2A2A) pedigree and to provide genetic counseling for its subsequent pregnancies.</p><p><strong>Methods: </strong>A Chinese pedigree presenting with \"lower limb muscle atrophy and movement disorders\" at the Prenatal Diagnosis Center of Xuzhou Central Hospital between January and August 2024 was selected as the study subject. Relevant clinical data were collected from the pedigree members. Peripheral blood samples from affected individuals, and amniotic fluid and/or chorionic villus samples were obtained for DNA extraction. Whole exome sequencing (WES) was carried out. Candidate variants were verified by Sanger sequencing. Pathogenicity assessment and bioinformatic analysis were conducted. This study was approved by the Medical Ethics Committee of Xuzhou Central Hospital (Ethics No. XZXY-LK-20240111-0019).</p><p><strong>Results: </strong>All affected individuals in this pedigree were females, whom included the proband, her mother, and her first daughter. Earlier age of onset was associated with more severe lower limb atrophy. A heterozygous missense variant of the MFN2 gene, namely c.314C>T (p.Thr105Met), was identified in the proband, her mother, daughter, and the third fetus from a re-marriage. The same variant was absent in her elder brother, current husband, and her fourth fetus. Based on the guidelines from American College of Medical Genetics and Genomics (ACMG) and recommendations from Clinical Genome Resources (ClinGen), the variant was classified as pathogenic (PP1_Strong+PM1+PS3+PS4_Moderate+PP3_Moderate+PM2_Supporting). Analyses with PROVEAN and Mutation Taster had categorized the variant as \"deleterious\" and \"disease-causing\", respectively. Analysis with Uniprot and Jalview showed that the affected amino acid residue is conserved across multiple species. ChEBI software predicted that the variant may alter the polarity of the 105th amino acid residue.</p><p><strong>Conclusion: </strong>The c.314C>T (p.Thr105Met) missense variant of the MFN2 gene probably underlie the CMT2A2A in this pedigree. Above finding has enabled prenatal diagnosis and genetic counseling for its subsequent pregnancies.</p>","PeriodicalId":39319,"journal":{"name":"中华医学遗传学杂志","volume":"42 1","pages":"74-81"},"PeriodicalIF":0.0,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142956460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}