The functional analysis of novel TSC1/2 mutations found in TSC patients

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K16528
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 48040:Medical biochemistry-related
• Research Institution: Kanazawa Medical University
• Principal Investigator: TOGI Sumihito 金沢医科大学, 総合医学研究所, 助教 (40709391)
• Project Period (FY): 2019-04-01 – 2021-03-31
• Keywords: TSC / スプライシング / 遺伝子検査 / iPS

Outline of Final Research Achievements

The genetic diagnosis of tuberous sclerosis complex is difficult because of its broad spectrum of mutations. In addition to point mutations in coding regions, intragenic or chromosomal-level large deletions, deep intronic splicing mutations, and mosaic mutations represent a significant proportion of the mutations. In this study, we focused on the splicing mutaitons, that has been missed by conventional genetic testing covering only genomic coding region of TSC1/2. And, we established the new genetic testing method, long-range PCR-based NGS analyses (CoLAS), that can be applied to detect various types of mutations simultaneously, using a single platform and multiplex PCR to reduce the experimental effort (J Mol Diagn. 2021).
Furthermore, we established TSC-patient derived iPS-cells for the functional analysis of the novel alternative splicing variants of TSC1/2 identified in TSC-patients. This is thought to be useful for understanding the molecular mechanism of developing TSC disease.

Free Research Field

臨床遺伝

Academic Significance and Societal Importance of the Research Achievements

本研究結果からTSC1/2のスプライシングバリアントには組織間や個体間で大きな多様性があり、それがTSC遺伝子の機能並びに疾患の重症度と深く結びついている可能性を見いだした。結節性硬化症は全身性の過誤腫病変を主とする遺伝性疾患であるが、その症状の現れ方や重症度には大きな個人差がある。一般的に遺伝子の機能はその発現量とタンパクの機能によって評価されるが、どのようなスプライシングバリアントがどのような割合で発現しているかも遺伝子機能を見る上で重要な情報となる。iPS細胞を用いた機能解析により、TSC1/2の新しい機能制御機構の解析、ならびに疾患の重症度や予後の予測に寄与できることが期待できる。