メラノコルチン1受容体アレルは,ネアンデルタール人の間で色素が異なることを示唆しています
Carles Lalueza-Fox1, Holger Römpler, David Caramelli
1Departament de Biologia Animal, Universitat de Barcelona, Spain. clalueza@ub.edu
Science (New York, N.Y.)
|October 27, 2007
まとめ
ネアンデルタール人は,メラノコルチン1受容体 (MC1R) に影響する遺伝子変異があり,色素に影響を与えました. これは,ネアンデルタール人の髪の毛と肌の色が現代人と同様の多様で,MC1Rの変異体による独立した進化があったことを示唆している.
科学分野:
- 遺伝学 遺伝学とは
- パレオントロジー・パレオントロジー
- 人間の進化 人類の進化
背景:
- メラノコルチン1受容体 (MC1R) は,脊椎動物における色素の調節に極めて重要です.
- MC1Rの機能の低下は,特にヨーロッパ系の人類の薄い肌と赤毛に関連しています.
研究 の 目的:
- ネアンデルタール人の遺体におけるMC1R遺伝子の変異を調べるために.
- 特定されたネアンデルタール人のMC1R変種が,肌の色素に与える機能的影響を決定する.
主な方法:
- ネアンデルタール人標本からのMC1R遺伝子断片の増幅と配列化.
- ネアンデルタール人のMC1R変異の比較分析を,現代のヒトの大規模なデータセットと比較した.
- ネアンデルタール人のMC1R変異の活性を評価するための機能検査.
主要な成果:
- 2人のネアンデルタール人の遺体で新しいMC1R変異が確認され, ~3700人の現代人には存在しない.
- 機能分析により,この変異体がMC1Rの活性を著しく低下させることが示されました.
- 活動が減少したことから,ネアンデルタール人の髪の毛や皮膚の色素が変化していたことが示唆される.
結論:
- ネアンデルタール人は,おそらく色素の変異を示していた.
- この発見は,現代のヒトとネアンデルタール人のMC1R変異の独立した進化を示唆しています.
- この研究は,ネアンデルタール人の外見の遺伝的根拠についての洞察を提供します.
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