人間のdel22q11.2症候群におけるTBX1の役割
Hisato Yagi1, Yoshiyuki Furutani, Hiromichi Hamada
1Division of Genomic Medicine, Institute of Advanced Biomedical Engineering and Science, Graduate School of Medicine, Tokyo Women's Medical University, Tokyo, Japan.
Lancet (London, England)
|October 31, 2003
まとめ
染色体22q11.2の切除は,一般的なマイクロ切除症候群を引き起こす. TBX1遺伝子変異は,完全な削除なしに,この症候群の重要な遺伝的原因として特定されています.
科学分野:
- 遺伝学 遺伝学とは
- 分子生物学は分子生物学である.
- 人間の病気 ヒトの病気
背景:
- 22q11.2消去症候群は,4000~5000人の生児の1人に発症する頻度の高いマイクロ消去症候群です.
- 心臓の欠陥,T細胞の欠乏,口腔裂け目,顔の異常,低カルシウム血症によって特徴付けられ,多数のマッピングされた遺伝子を持つ染色体22q11.2の3Mbの削除が含まれています.
- これらの遺伝子のシンドロームを引き起こす正確な役割は不明である.
研究 の 目的:
- 22q11.2消去症候群の遺伝的基礎を調査する.
- TBX1遺伝子の変異が症候群の表型に寄与するかどうかを判断する,特に典型的な削除のない個体において.
主な方法:
- 22q11.2に10個のプローブを用いた光インシトゥハイブリデーション (FISH) 分析は,del22q11.2症候群と診断された235人の患者に実施されました.
- TBX1のコード配列の遺伝子解析は,22q11.2症候群のフェノタイプを示した13人の患者に実施したが,検出可能な欠損が欠如していた.
主要な成果:
- 22q11.2で定義された1.5-3Mbのデリエーションは,患者の96% (225/235) で確認されました.
- TBX1の3つの突然変異は,22q11.2の削除のない2人の無関係な患者で特定され,顔/ベロカーディオファシアル症候群またはディジョージ症候群のコノトランカル異常を示した.
- これらの変異は,コノトランカル異常顔/ベロカーディオファシアル症候群の家族から3人の患者でも発見され,555人の健康な対照群 (p<0.0001) では見られなかった.
結論:
- TBX1変異は,22q11.2消去症候群に関連した5つの主要な表型の原因に関与しています.
- この研究では,TBX1が22q11.2消去症候群の重要な遺伝的決定因子であると結論づけています.
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