クロスオーバーの高解像度マッピングは,ヒトの間で微細な再結合パターンの広範な変化を明らかにしています
Graham Coop1, Xiaoquan Wen, Carole Ober
1Department of Human Genetics, University of Chicago, 920 East 58th Street, Cummings Life Science Center, Chicago, IL 60637, USA. gcoop@uchicago.edu
Science (New York, N.Y.)
|February 2, 2008
まとめ
人間の再結合パターンは,個別の有意な変化を示しています. 交差点では,ミオシス中の染色体分離に不可欠なクロスオーバーが起こりますが,これらのホットスポットの使用は個体によって異なります.
科学分野:
- 遺伝学 遺伝学とは
- ヒューマンゲノミクスは,ヒトゲノミクスです.
- 分子生物学は分子生物学である.
背景:
- 再結合は,メオシス中の正確な染色体分離に不可欠です.
- 以前の研究では,ヒトゲノム全体で再結合率の有意な変動が特定ホットスポットに集中していることを示しています.
- 微細な再結合パターンの理解は,ゲノム安定性と遺伝を理解する上で鍵となる.
研究 の 目的:
- ヒトゲノム全体で微細な再結合パターンの個々の変動を調査する.
- 再結合ホットスポットの使用における遺伝的変動の範囲を決定するために.
- 男性と女性の再結合パターンを比較する.
主な方法:
- 核家族から集約された,全ゲノムにわたる単核性多形態化 (SNP) データを利用した.
- クロスオーバーイベントの高解像度マッピングを使用した.
- 結合不均衡 (LD) データを用いて推測された再結合ホットスポット.
主要な成果:
- 再結合ホットスポットの使用は,男性と女性の間でほぼ同じで,多くのホットスポットが両方の性別で活発です.
- すべてのクロスオーバーの約60%は,LD研究で特定されたホットスポット内で発生しました.
- 男性と女性の両方のホットスポットで発生するクロスオーバーの割合において,有意で遺伝的な変動が観察されました.
結論:
- リコンビネーションホットスポット利用の個々の変動は,ヒトゲノムの顕著な特徴です.
- この変異は遺伝性であり,再結合パターンの遺伝的コントロールを示唆している.
- 再結合パターンは,一般的にホットスポットで保存されているが,メオシスと遺伝に影響を与える実質的な個人的変化を示している.
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