チンパンジーのHIV-1の起源 パントログロディテス トログロディテス
F Gao1, E Bailes, D L Robertson
1Department of Medicine, University of Alabama at Birmingham, 35294, USA.
Nature
|February 16, 1999
まとめ
中央のチンパンジー亜種 (Pan troglodytes troglodytes) は,ヒト免疫不全ウイルス1型 (HIV-1) の主要な貯蔵庫である. この亜種は,類人猿の免疫不全ウイルス (SIVcpz) の少なくとも3つの独立したヒトへの動物性感染症の発生源となっている.
科学分野:
- ウイルス学 ウイルス学 ウイルス学
- プリマトロジー・プリマトロジー学
- 進化生物学の進化生物学について
- 動物性感染症 動物性感染症
背景:
- ヒト免疫不全ウイルス (HIV-1およびHIV-2) は,人間以外の霊長類に由来する動物性感染症です.
- HIV-2のシミアン免疫不全ウイルス (SIV) 貯蔵庫は,ソティ・マンガベイと特定されているが,HIV-1の起源は不明である.
- 以前の研究では,HIV-1に関連したチンパンジーにおける類人猿の免疫不全ウイルス (SIVcpz) が特定されましたが,文書化された感染はまれで異なるものでした.
研究 の 目的:
- HIV-1の天然貯蔵庫を特定する.
- SIVcpz株の進化的起源と伝播ダイナミクスを調査する.
- SIVcpzに感染したチンパンジーの亜種を特定し,HIV-1との遺伝関係を明らかにする.
主な方法:
- 新型SIVcpz株 (SIVcpzUS) のゲノムシーケンシング.
- SIVcpzに感染したチンパンジーの亜種を決定するためのミトコンドリアDNA分析.
- SIVcpzおよびHIV-1株の系統遺伝分析.
主要な成果:
- 中部 (P. t. troglodytes) と東部 (P. t. schweinfurthii) の2つのチンパンジー亜種には,異なるSIVcpz系統がある.
- 既知のヒトHIV-1株 (M,N,O群) はすべて,P. t. トログロダイテスに見られるSIVcpz系統と密接に関連している.
- HIV-1グループNは,チンパンジーの宿主における再結合を示し,モザイク配列を示しており,その自然範囲はHIV-1流行地域と重なり合っている.
結論:
- 中央のチンパンジー亜種 (Pan troglodytes troglodytes) は,HIV-1の主要な貯蔵庫となっている.
- SIVcpzがP. t. トログロダイトからヒトへの3つの独立した動物性感染症の感染が起きました.
- チンパンジーのSIVcpz貯蔵庫を理解することは,HIV-1の将来的な動物性感染症の伝播を防ぐために非常に重要です.
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