免疫 遺伝子 の 進化 は ブラック デス と 関連 し て い ます
Jennifer Klunk1,2, Tauras P Vilgalys3, Christian E Demeure4
1McMaster Ancient DNA Centre, Departments of Anthropology, Biology and Biochemistry, McMaster University, Hamilton, Ontario, Canada.
Nature
|October 19, 2022
まとめ
免疫系の遺伝子を選択することで ヒトの進化を促しました 特定の遺伝的変異はYersinia pestisに対する抵抗性を高めましたが,今日では自己免疫疾患のリスクを高める可能性があります.
科学分野:
- 人間の進化遺伝学
- パレオゲノミクス
- 免疫学
背景:
- 伝染病 特にイエルシニア・ペスティスによる ブラック・デスのようなパンデミックは 人間の進化の重要な原動力です
- ブラック・デス・パンデミックは前例のない死亡率を引き起こし,アフリカ・ユーラシア人の30~50%を殺しました.
研究 の 目的:
- ブラック・デス・パンデミックで 選択された遺伝子の位置を特定するためです
- ヒトゲノムに対する イエルシニア・ペスティスの進化的影響を 研究する
主な方法:
- ヨーロッパ人集団の206の古代DNAサンプルから 免疫関連遺伝子の遺伝的変異の分析
- 免疫と非免疫のロシウムの遺伝的差異の比較
- 独立したデンマークのコホートでの発見の複製.
主要な成果:
- 免疫ロシオは高度に差別化された部位で有意な濃縮を示し,ポジティブな選択を示した.
- ロンドン・コホートでは245の高度に差別化された変種が特定され,デンマーク・コホートでは4つの変種が複製されました.
- 特定の変種 (rs2549794) は,ERAP2のトランスクリプト生成,Y. pestisのサイトカイン応答,および細胞内病原体制御と関連していた.
結論:
- 過去のパンデミックは ヒトの免疫系の進化を形作り 検出可能な遺伝子シグネチャを残しました
- 歴史的な病原体に対する耐性を付与する遺伝的変異は,現代の自己免疫疾患に対する感受性に影響を与える可能性があります.
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