基础医学与临床 ›› 2024, Vol. 44 ›› Issue (3): 361-367.doi: 10.16352/j.issn.1001-6325.2024.03.0361

• 研究论文 • 上一篇    下一篇

结节性硬化症5个家系致病变异的鉴定

刘思邑, 杨玉姣, 杨涛*, 赵秀丽*   

  1. 中国医学科学院基础医学研究所 北京协和医学院基础学院 医学遗传学系疑难重症及罕见病全国重点实验室,北京 100005
  • 收稿日期:2023-11-08 修回日期:2024-01-05 出版日期:2024-03-05 发布日期:2024-02-22
  • 通讯作者: *:tyang@ibms.pumc.edu.cn; xiulizhao@ibms.pumc.edu.cn
  • 基金资助:
    中国医学科学院医学与健康科技创新工程(2021-I2M-1-051,2021-I2M-1-053)

Identification of the causative variants in five Chinese families with tuberous sclerosis complex

LIU Siyi, YANG Yujiao, YANG Tao*, ZHAO Xiuli*   

  1. Department of Medical Genetics, State Key Laboratory for Complex, Severe, and Rare Diseases, Institute of Basic Medical Sciences CAMS, School of Basic Medicine PUMC, Beijing 100005, China
  • Received:2023-11-08 Revised:2024-01-05 Online:2024-03-05 Published:2024-02-22
  • Contact: *:tyang@ibms.pumc.edu.cn; xiulizhao@ibms.pumc.edu.cn

摘要: 目的 对5个结节性硬化症(TSC)家系进行致病变异鉴定,为相关家系的遗传咨询和产前诊断提供依据。方法 选取2020年1月至2021年7月间在中国医学科学院基础医学研究所进行远程遗传咨询的5个无关TSC家系的8例患者为研究对象;抽取患者及其家系成员静脉外周血3~5 mL,应用常规酚/氯仿法提取基因组DNA;通过panel测序(PS)发现候选致病变异,经PCR-Sanger测序验证并联合生物信息学分析对先证者及其家系成员进行TSC1/TSC2致病变异鉴定。结果 5个TSC家系患者均存在TSC1或TSC2的变异,包括3个已报道致病变异和2个新发现的疑似致病变异。2个新变异,TSC2: c.245G>A和TSC2: c.235delG,预测可分别造成无义变异p.(Trp82*)和移码变异p.(Val79Lysfs27*),形成提前终止密码子,并经家系共分离和生物信息学分析判定为致病性变异。结论 本研究为相关家庭的遗传咨询和产前诊断提供了依据,进一步拓展了TSC2致病变异谱。

关键词: 结节性硬化症, TSC1, TSC2, 新致病变异

Abstract: Objective To identify the causative variants in 5 Chinese families with tuberous sclerosis complex (TSC) to provide genetic counseling and prenatal diagnosis. Methods Genetic counseling and clinical diagnosis were performed in 8 patients from five unrelated TSC families by teleconsultation. With informed consent obtained from the participants, 3 to 5 mL peripheral blood samples were collected from the probands and their family members for the extraction of genomic DNA. Candidate pathogenic variants were screened by panel sequencing (PS). The candidate pathogenic variants found in TSC1 and TSC2 by PS were validated by PCR-Sanger sequencing and bioinformatics analysis. Results All the pathogenic mutations were identified in the probands and their available family members. Causative variants in TSC1 or TSC2 were detected in all patients, including three reported variants and two novel variants. The two novel variants, TSC2:c.245G> A and TSC2: c.235delG, which were predicted to cause the nonsense variant p.(Trp82*) and the frameshift variant p.(Val79Lysfs27*) respectively was believed to introduce premature stop codons. The analysis of family co-segregation and bioinformatics were identified as very positive factors for pathogenicity. Conclusions This result provides more evidences for the genetic counseling and prenatal diagnosis in these families and expand the spectrum of TSC2 pathogenic variants.

Key words: tuberous sclerosis complex, TSC1, TSC2, novel pathogenic variant

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