バクテリアの視点から太平洋の定住
Yoshan Moodley1, Bodo Linz, Yoshio Yamaoka
1Max-Planck-Institut für Infektionsbiologie, Department of Molecular Biology, Charitéplatz 1, 10117 Berlin, Germany.
まとめ
太平洋を横断した2つの史前の人間の移住は,異なるヘリコバクター・ピロリ菌株,hpSahulとhspMaoriをもたらしました. これらの古代の病原菌の系統は,人間の集団と共進化し,移住パターンと孤立を反映した.
科学分野:
- 遺伝学と進化生物学について
- アントロポロジー人類学
- 微生物学 微生物学とは
背景:
- 太平洋地域は,2つの主要な史前の人類の移住によって人口が増加した.
- これらの移住は,ヒトの病原体ヘリコバクター・ピロリ (Helicobacter pylori) の2つの異なる系統:hpSahulとhspMaoriを導入した.
研究 の 目的:
- 太平洋におけるヘリコバクター・パイロリ菌群の起源と拡散を追跡する.
- H. pyloriの遺伝的分岐をヒトの移住イベントと相関させるため.
主な方法:
- ヘリコバクター・パイロリ菌株の系統遺伝分析.
- 遺伝的差異を考古学および言語学的データと比較.
主要な成果:
- hpSahulの集団は,31,000~37,000年前にアジア系H. pyloriから分離し,ニューギニアとオーストラリアへの早期の人類の移住と一致した.
- hpニューギニアとオーストラリアのサフルの集団は,23,00032,000年の隔離を示し,分岐を示しています.
- hspマオリ族は,台湾のオーストラリア語話者と共に約5,000年前に分散し,メラネシアとポリネシアで共進化した.
結論:
- ヘリコバクター・ピロリ菌群は,太平洋における史前の人間の移住を再構築するための信頼できるマーカーとして機能します.
- hpSahulとhspMaoriのヒト宿主との共同進化は,古代の人口移動と孤立の出来事についての洞察を提供します.
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