自然選択は,ドロソフィラ・メラノガスターの複製数多型性の全ゲノム規模のパターンを形作る
J J Emerson1, Margarida Cardoso-Moreira, Justin O Borevitz
1Department of Ecology and Evolution, University of Chicago, Chicago, IL 60637, USA. jje@uchicago.edu
まとめ
自然選択は果物ハエの複製数の変異を形作る. 浄化選択は消去部位に強く影響し,陽性選択は毒素反応遺伝子の重複を好む.
科学分野:
- ゲノミクスゲノミクスとは
- 進化生物学の進化生物学について
- 人口遺伝学 人口遺伝学
背景:
- 複製数変異の進化に対する自然選択の影響は十分に理解されていません.
- コピー数ポリモルフィズム (CNP) は,重要な進化的意味を持つ遺伝的多様性の源である.
研究 の 目的:
- ゲノム分布の形成とコピー数変異の初期進化における自然選択の役割を調査する.
- ドロソフィラ・メラノガスターのCNPの高解像度マップを作成し,その進化動態を分析する.
主な方法:
- 総合的なゲノム分析のための高密度,全ゲノムタイリング配列を使用しました.
- ゲノム全体にわたる独立した複製数ポリモルフィズム (CNP) の大きなセットを推論した.
主要な成果:
- 2658の独立したCNPを特定し,56%の遺伝子が重複しています.
- 高頻度複製,特に毒素反応遺伝子を含む複製において,ポジティブ・セレクションの証拠を観測した.
- 精製選択がCNPの位置を強く形作ることを実証し,削除は重複よりも強い選択を経験しました.
結論:
- 自然選択は,複製数変異の進化とゲノム組織において重要な役割を果たします.
- 浄化選択は,複製よりも消去に強く作用し,重複する遺伝子やX染色体にある複製に強く作用する.
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