デノボ変異は,遺伝性運動および感覚神経症I型におけるデノボ変異である
J E Hoogendijk1, G W Hensels, A A Gabreëls-Festen
1Department of Neurology, Academic Medical Center, Amsterdam, The Netherlands.
Lancet (London, England)
|May 2, 1992
まとめ
ほとんどの孤立したシャルコ・マリー・トゥース1型 (HMSN I) 症例は,現在,自己相性優位性であると理解されています. 支配的なHMSN Iの一般的な原因である染色体17の重複は,ほとんどの散発的な患者で新しい変異として現れ,遺伝カウンセリングに影響を与えます.
科学分野:
- 遺伝学 遺伝学とは
- 神経学 神経学とは
- 分子生物学は分子生物学である.
背景:
- 遺伝性運動および感覚神経症I型 (HMSN I) は,シャルコ・マリー・トゥース病1型とも呼ばれ,外周神経系の疾患である.
- 以前は,HMSN Iの孤立した症例は,しばしば自己相性後退性であると推定されていました.
- 最近の研究では,17号染色体の特定の重複が,自己相性優位性HMSN I.の主要な原因として特定されました.
研究 の 目的:
- HMSN I.の散発的な (孤立した) 症例の遺伝的根拠を調査する.
- 孤立したHMSN I.を呈する患者における染色体17重複の頻度を測定する.
- HMSN I.における遺伝カウンセリングにおける遺伝パターンの明確化と影響を明らかにする.
主な方法:
- スポラディックなHMSN I患者の遺伝分析.
- 既知の染色体17重複のスクリーニングは,自己相性支配的HMSN I. I. と関連しています.
- スポラディック対ファミリアルHMSN I症例における遺伝的発見の比較.
主要な成果:
- 染色体17の複製のde-novo (新しい) 変異は, sporadic HMSN I患者の90% (10人中9人) で特定されました.
- この発見は,単離されたHMSN I.で頻繁に発生する自己相性後退性遺伝に関する以前の仮定に異議を唱える.
- 特定された変異は,HMSN I.のほとんどの自己相性支配的形態に起因する同じ重複である.
結論:
- 散発的なHMSN I症例の大部分は,de-novo自己相性優位変異,特に染色体17重複によって引き起こされます.
- この遺伝的発見は,単離されたHMSN I.を有する個体に対する遺伝カウンセリング戦略の再評価を必要とします.
- デノボ変異の発生率を理解することは,正確な遺伝的リスク評価と家族計画に不可欠です.
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