ヒトと果物ハエの陰性選択は,シネジスティックなエピスタシスを含みます
Science (New York, N.Y.)
|May 6, 2017
まとめ
有害な遺伝子変異に対する 負の選択は シンर्जी効果を示し,つまり 追加の変異が 適性を著しく低下させる. このヒトとハエの集団の発見は 高い変異率にもかかわらず 種が存続する理由を説明するのに役立ちます
科学分野:
- 進化生物学
- 集団遺伝学
- ゲノミクス
背景:
- 有害なアレルに対するネガティブな選択は,集団内の変動の主な要因である.
- 複数の有害アレルによる体格低下の性質 (独立性 vs シネジスティック性) は不明である.
研究 の 目的:
- 有害なアレルが独立して,あるいは相乗効果で体調に影響するかどうかを調べる.
- 希少な機能喪失アレルに対する選択の特徴であるかどうかを判断する.
主な方法:
- 人間とハエの8つの独立データセットの分析
- 希少な機能喪失アレルの分布における低分散の検出
主要な成果:
- すべてのデータセットで希少な機能喪失アレルの低分散が検出されました.
- この低分散は,有害なアレル間の相乗効果エピスタシスを示す.
結論:
- 希少なタンパク質破壊性アレルに対する選択は,シネジスティックなエピスタシスを示す.
- 合成エピスタシスは,高いゲノム変異率にもかかわらず,集団の持続のためのメカニズムを提供します.
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