SCN9Aチャネル病変は,先天的に痛みを感じる能力が欠如することを引き起こします
James J Cox1, Frank Reimann, Adeline K Nicholas
1Department of Medical Genetics, Cambridge Institute for Medical Research, Wellcome/MRC Building, Addenbrooke's Hospital, Cambridge CB2 0XY, UK.
Nature
|December 15, 2006
まとめ
痛みを感じることが全くできない人は,珍しい遺伝疾患を持っています. この研究は,痛みのシグナル伝達に不可欠なSCN9A遺伝子の3つの新しい変異を特定し,この痛みの無感性を説明しています.
科学分野:
- 遺伝学 遺伝学とは
- 神経科学は神経科学である.
- 分子生物学は分子生物学である.
背景:
- 痛みに対する先天性無感覚は,極めてまれな状態です.
- 痛みの知覚は,ノシセプターと呼ばれる特殊な感覚神経細胞によって主に媒介されます.
研究 の 目的:
- パキスタンの3つの家族の痛みに対する先天性無感性の遺伝的根拠を調査する.
- 痛みの感覚の喪失に起因する特定の遺伝子と突然変異を特定する.
主な方法:
- 遺伝子を染色体2q24.3.3.にマッピングするための全ゲノム関連分析.
- 感染した個体におけるSCN9A遺伝子のサンガー配列解析.
- 特定されたSCN9A変異の機能的特徴付けは,HEK293細胞における異質的発現を用いて行われます.
主要な成果:
- 感染した個体におけるSCN9A遺伝子の3つの異なった同同位体の無意味な変異 (S459X,I767X,W897X) を特定した.
- これらの変異は,Na ((v) 1.7ナトリウムチャネルの機能の完全な喪失につながることを実証しました.
- 変異したNa (v) 1.7チャネルを発現する細胞で測定可能なイオンチャネル活動は観察されなかった.
結論:
- Na(v) 1.7チャネルをコードするSCN9A遺伝子は,ヒトの知覚に不可欠であり,冗長ではない.
- SCN9Aの機能喪失変異は,痛みに先天的な無感性を引き起こします.
- これらの発見は,Na(v) 1.7チャネルを標的とした新しい鎮痛剤を開発するための基礎を提供します.
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