Background: SH3TC2, PMP2, and BSCL2 genes are related to autosomal recessive (AR) Charcot-Marie-Tooth (CMT) disease type 1, autosomal dominant (AD)-CMTI, and AD-CMT2, respectively. Pathogenic variants in these ...Background: SH3TC2, PMP2, and BSCL2 genes are related to autosomal recessive (AR) Charcot-Marie-Tooth (CMT) disease type 1, autosomal dominant (AD)-CMTI, and AD-CMT2, respectively. Pathogenic variants in these three genes were not well documented in Chinese CMT patients. Therefore, this study aims to detect SH3TC2, PMP2, and BSCL2 pathogenic variants in a cohort of 315 unrelated Chinese CMT families. Methods: A total of 315 probands from 315 unrelated Chinese CMT families were recruited from the Department of Neurology of Third Xiangya Hospital and Xiangya Hospital. We screened for SH3TC2 pathogenic variants in 84 AR or sporadic CMT probands, PMP2 pathogenic variants in 39 AD or sporadic CMTI probands, and BSCL2 pathogenic variants in 50 AD or sporadic CMT2 probands, using polymerase chain reaction and Sanger sequencing. All these patients were out of 315 unrelated Chinese CMT families and genetically undiagnosed after exclusion of pathogenic variants of PMP22, MFN2, MPZ, GJB 1, GDAP1, HSPB1, HSPB8, EGR2, NEFL. and RABT. Candidate variants were analyzed based on the standards and guidelines of American College of Medical Genetics and Genomics (ACMG). Clinical features were reevaluated. Results: We identified three novel heterozygous variants such as p.L95V (c.283C〉G), p.L 1048P (c.3143T〉C), and p.V 1105 M (c.3313G〉A) of SH3TC2 gene and no pathogenic variants of PMP2 and BSCL2 genes. Although evaluation in silico and screening in the healthy control revealed that the three SH3TC2 variants were likely pathogenic, no second allele variants were discovered. According to the standards and guidelines of ACMG, the heterozygous SH3TC2 variants such as p.L95V, p.LI048P, and p.V1105M were considered to be of uncertain significance. Conclusions: SH3TC2, PMP2, and BSCL2 pathogenic variants might be rare in Chinese CMT patients. Further studies to confirm our findings are needed.展开更多
远端型遗传性运动神经病(distal hereditary motor neuropathy,dHMN)是罕见的遗传性周围神经病,由于其发病率低,临床表现异质性强,临床易误诊或漏诊。本文报告1例可疑远端型遗传性运动神经病。患者发病十年,以隐匿性肢体无力起病,伴有...远端型遗传性运动神经病(distal hereditary motor neuropathy,dHMN)是罕见的遗传性周围神经病,由于其发病率低,临床表现异质性强,临床易误诊或漏诊。本文报告1例可疑远端型遗传性运动神经病。患者发病十年,以隐匿性肢体无力起病,伴有肌肉萎缩,无感觉异常,神经科查体及神经电生理检查均提示为远端对称性运动纤维轴索损害,详细分析患者临床资料及神经电生理检查特点,符合远端型遗传性运动神经病的特点,基因筛查提示患者有BSCL2基因突变。经营养神经等对症治疗,随访将近1年,患者临床症状及电生理检查无明显进展。该病例提示临床工作中应注意遗传性周围神经病的可能,善于分析临床及电生理检查资料,必要时采用基因诊断,做到早发现、早确诊。展开更多
文摘Background: SH3TC2, PMP2, and BSCL2 genes are related to autosomal recessive (AR) Charcot-Marie-Tooth (CMT) disease type 1, autosomal dominant (AD)-CMTI, and AD-CMT2, respectively. Pathogenic variants in these three genes were not well documented in Chinese CMT patients. Therefore, this study aims to detect SH3TC2, PMP2, and BSCL2 pathogenic variants in a cohort of 315 unrelated Chinese CMT families. Methods: A total of 315 probands from 315 unrelated Chinese CMT families were recruited from the Department of Neurology of Third Xiangya Hospital and Xiangya Hospital. We screened for SH3TC2 pathogenic variants in 84 AR or sporadic CMT probands, PMP2 pathogenic variants in 39 AD or sporadic CMTI probands, and BSCL2 pathogenic variants in 50 AD or sporadic CMT2 probands, using polymerase chain reaction and Sanger sequencing. All these patients were out of 315 unrelated Chinese CMT families and genetically undiagnosed after exclusion of pathogenic variants of PMP22, MFN2, MPZ, GJB 1, GDAP1, HSPB1, HSPB8, EGR2, NEFL. and RABT. Candidate variants were analyzed based on the standards and guidelines of American College of Medical Genetics and Genomics (ACMG). Clinical features were reevaluated. Results: We identified three novel heterozygous variants such as p.L95V (c.283C〉G), p.L 1048P (c.3143T〉C), and p.V 1105 M (c.3313G〉A) of SH3TC2 gene and no pathogenic variants of PMP2 and BSCL2 genes. Although evaluation in silico and screening in the healthy control revealed that the three SH3TC2 variants were likely pathogenic, no second allele variants were discovered. According to the standards and guidelines of ACMG, the heterozygous SH3TC2 variants such as p.L95V, p.LI048P, and p.V1105M were considered to be of uncertain significance. Conclusions: SH3TC2, PMP2, and BSCL2 pathogenic variants might be rare in Chinese CMT patients. Further studies to confirm our findings are needed.
文摘远端型遗传性运动神经病(distal hereditary motor neuropathy,dHMN)是罕见的遗传性周围神经病,由于其发病率低,临床表现异质性强,临床易误诊或漏诊。本文报告1例可疑远端型遗传性运动神经病。患者发病十年,以隐匿性肢体无力起病,伴有肌肉萎缩,无感觉异常,神经科查体及神经电生理检查均提示为远端对称性运动纤维轴索损害,详细分析患者临床资料及神经电生理检查特点,符合远端型遗传性运动神经病的特点,基因筛查提示患者有BSCL2基因突变。经营养神经等对症治疗,随访将近1年,患者临床症状及电生理检查无明显进展。该病例提示临床工作中应注意遗传性周围神经病的可能,善于分析临床及电生理检查资料,必要时采用基因诊断,做到早发现、早确诊。