アンダマン諸島の住民の起源を再構築する
Kumarasamy Thangaraj1, Gyaneshwer Chaubey, Toomas Kivisild
1Centre for Cellular and Molecular Biology, Hyderabad-500 007, India.
まとめ
アンダマン"ネグリト"とニコバル"モンゴロイド"の集団
科学分野:
- 人間の進化遺伝学
- 集団遺伝学 人口遺伝学
- 古代のDNA分析について
背景:
- アンダマン・ニコバル諸島の住民の起源は,歴史的に曖昧である.
- 以前の研究は,これらの孤立したコミュニティの遺伝的系統に関する限られた洞察を提供してきました.
研究 の 目的:
- アンダマン"ネグリト"とニコバル"モンゴロイド"の人口の深い祖先の起源を調査する.
- これらの島群の移住パターンと遺伝的孤立を明らかにする.
主な方法:
- アンダマン (オンゲ,グレート・アンダマン) とニコバル諸島の個体からの完全なミトコンドリアDNA (mtDNA) 配列の分析.
- 系統遺伝分析により,根深いクラードと共通の祖先を決定する.
- 移住の歴史を推論するために,mtDNA系統と世界の人口の比較.
主要な成果:
- アンダマン諸島の集団で,創始ハプログループM.から生まれた2つの異なる,深く枝分かれしたmtDNAクラードが特定されました.
- これらのアンダマン諸島のクラッドは,インド,アフリカ,東アジア,ニューギニア,オーストラリアで発見された系統とのつながりを示しています.
- ニコバラのmtDNA配列は,東南アジアの集団との密接な遺伝的親和性を明らかにしました.
結論:
- アンダマンのmtDNAの系統は,解剖学的に現代的な人間による初期の"アフリカからの"移住以来,遺伝的孤立の中で生存することを示唆しています.
- 遺伝データは,ニコバラ人の独特の祖先の歴史を裏付け,東南アジアの人口と密接に結びついています.
- ミトコンドリアDNA分析は,アンダマン・ニコバル諸島の人口に関する重要な洞察を提供します.
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