繰り返し進化し,アミラーゼの場所での選択形状の構造多様性
Davide Bolognini1, Alma Halgren2, Runyang Nicolas Lou2
1Human Technopole, Milan, Italy.
Nature
|September 4, 2024
まとめ
農業革命により ヒトのアミラーゼ遺伝子の複製が多くなり 粉の消化に役立ちました この遺伝子の複製は ポジティブ・セレクションによって引き起こされ 過去"万2千年の間に 頻度が急速に増加しました
科学分野:
- 人間 の 進化 的 な 遺伝子
- ゲノミクス
- 考古学 科学
背景:
- 農業への移行により 人々の食生活は劇的に変化し 粉への依存が増加しました
- アミラーゼ遺伝子は粉の消化に不可欠であり,コピー番号の変動は食事習慣に関連しています.
- アミラーゼ遺伝子複製数の最近の選択に関する以前の証拠は限られていた.
研究 の 目的:
- アミラーゼの位置における構造的変異の多様性と進化史を調査する.
- 農業革命がヒトのアミラーゼ遺伝子の複製数に与える影響を理解するためです
- アミラゼ遺伝子の構造的変異に作用する選択の証拠を特定する.
主な方法:
- 94の長読ハプロタイプ解析アセンブリと約5,600の短読ヒトゲノムデータ (現代と古代) の分析.
- パンゲノムベースのアプローチで,多様なヒト集団の構造的ハプロタイプを推論する.
- ヒトゲノム533個を活用して ハプロタイプ頻度の変化を 12,000年にわたって追跡した
主要な成果:
- 類似した構造の繰り返し進化を伴う 28 つの異なるアミラーゼ遺伝子構造構造を特定した.
- 農業集団は,非農業集団と比較して,より高いアミラーゼ遺伝子コピー数を示しています.
- 複製を含むハプロタイプは,遺伝子の複製の増加と関連しており,過去1万2千年にわたって西ユーラシア人の頻度が急速に上昇しました.
結論:
- ヒトのアミラーゼ遺伝子の複製数と構造は,農業革命以来,著しい適応を経験しています.
- アミラーゼの位置における構造的変異は,食事の変化に反応するポジティブな選択の強いシグナルを示している.
- この研究は,主要なライフスタイルの変化に人間の適応における構造的変化の役割を強調しています.
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