ヒトゲノムにおけるコピー数変化の起源と機能的影響
Donald F Conrad1, Dalila Pinto, Richard Redon
1The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA UK.
Nature
|October 9, 2009
まとめ
この研究は,ヒトゲノムにおける11,000以上の複製数変異 (CNV) をマッピングし,その変異メカニズムと疾患の感受性との潜在的な関連を明らかにしています. 一般的なCNVは,全ゲノム関連研究で特定された複雑な特徴の遺伝性のギャップを説明しません.
科学分野:
- ゲノミクスゲノミクスとは
- ヒューマン・ジェネティクス ヒューマン・ジェネティックス
- 分子生物学は分子生物学である.
背景:
- 構造的変異,特にコピー数変異 (CNVs) >1キロベースは,ヒトゲノム多様性の重要な源である.
- CNVは,ゲノム多様性に対する実質的な影響にもかかわらず,十分に評価されていません.
- CNVの分布と起源を理解することは,ヒト遺伝学研究にとって極めて重要です.
研究 の 目的:
- 人間のゲノムにおける複製数変異 (CNVs) の包括的な地図を作成する.
- 異なるCNVサイズクラスの基礎となる変異メカニズムを調査する.
- 疾患の感受性に関連したCNVを特定し,複雑な特性の遺伝性への貢献を評価する.
主な方法:
- CNVを検出するための4200万個の探知器を備えたタイル式オリゴヌクレオチドマイクロアレイを使用しました.
- 独立した方法によって,多数の特定されたCNVを検証しました.
- 異なる祖先集団 (ヨーロッパ,アフリカ,東アジア) の何千ものCNVのリファレンス遺伝子タイプを生成しました.
主要な成果:
- 11,700 CNV (>443 塩基対) のマップを作成し,8,599 が独立して検証されました.
- レトロトランスポーゼーションを含む,異なるCNVサイズクラスにおける異なる変異メカニズムを特定した.
- CNVsが特質関連単核酸多形態 (SNP) と相関する30の位置を発見し,疾患の感受性における潜在的な役割を示唆しました.
結論:
- この研究は,ヒトゲノム変異の研究に貴重なリソースを提供します.
- 共通のCNVは,複雑な特性の全ゲノム関連研究で観察された遺伝性のギャップを説明しません.
- 人間の病気における構造的変異の役割を完全に理解するためには,さらなる研究が必要である.
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