家养动物起源研究不仅具有其自身的意义,而且对于了解人类社会的发展也十分重要。虽然有证据显示家猪在全世界多个地方独立起源,但家猪在东亚的具体起源地点和扩散路径并不是很清楚。近期,昆明动物研究所遗传资源与进化国家重点实验室张亚平院士研究小组对东亚野猪和家猪的线粒体群体基因组进行了分析,研究表明所有东亚家猪来源于单一世系D,且东亚家猪的驯化主要发生在湄公河流域和长江中下游流域。该研究成果于11月19日发表在国际著名刊物《基因组生物学(Genome Biology)》上(http://genomebiology.com/content/pdf/gb-2007-8-11-r245.pdf )
群体基因组学是目前解决群体遗传结构、多样性和系统地理分化的最佳手段,但昂贵的测序费用使得群体基因组学仍然只是未来的发展趋势。吴桂生、张亚平及其合作者通过分析家猪和野猪线粒体控制区序列得到初步的系统发育信息,并在此基础上选取代表不同世系的个体进行线粒体全序列测定,首次构建了基于线粒体全序列的具有广泛代表性的东亚家猪和野猪的系统发育关系树。该系统树为进一步归类划分东亚野猪和家猪mtDNA世系提供了依据和蓝图。基于建立的这一系统,该小组描绘出高分辨率的东亚家猪和野猪mtDNA系统发育地理图,推断出东亚野猪的系统地理分化和家猪的起源分化等群体历史事件。他们的研究显示东亚野猪很可能起源于湄公河流域,分两路扩散,一条由西南向北到青海、甘肃、新疆等地,一路向东到达长江中下游流域后在向东北扩散,最后到达东北亚。所有东亚家猪可溯祖至同一世系D,其中包含有多个支系.并分别在湄公河流域和长江中下游流域得到驯化。类似于野猪的扩散模式,在湄公河流域驯化的家猪主要经西南向北扩散到青海、甘肃、新疆等地,而在长江中下游流域驯化的家猪主要向东北扩散。
该项研究不仅揭示了东亚野猪和家猪的起源分化事件,使人们对古代东亚农业文明的形成有了进一步的认识,而且其研究策略为相关的家养动物驯化研究提供了很好的借鉴。(昆明动物所)
原始出处:
Population phylogenomic analysis of mitochondrial DNA in wild boars and domestic pigs revealed multiple domestication events in East Asia
Gui-Sheng Wu1, 2, 3, 4, Yong-Gang Yao1,5, Kai-Xing Qu1, Zhao-Li Ding2, Hui Li1, Malliya
G Palanichamy2, Zi-Yuan Duan1, Ning Li6, Yao-Sheng Chen7, Ya-Ping Zhang1, 2*
1 State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of
Zoology, Chinese Academy of Sciences, Kunming 650223, China; 2 Laboratory for
Conservation and Utilization of Bio-resource, Yunnan University, Kunming 650091,
China; 3 The Graduate School of the Chinese Academy of Sciences, Beijing, 100039,
China; 4 Current address: Center for Pharmacogenomics, Department of Psychiatry and
Behavioral Science, University of Miami Miller School of Medicine, Miami FL 33136,
USA; 5 Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming
Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China; 6 China
Agriculture University, Beijing 10094, China; 7 College of Life Sciences, Sun Yat-sen
University, Guangzhou 510275, China
*Corresponding author: Dr. Ya-Ping Zhang
State Key Laboratory of Genetic Resources and Evolution,
Kunming Institute of Zoology, the Chinese Academy of Sciences,
Kunming, Yunnan 650223, China
PHONE: (+86) 871-519 8993; FAX: (+86) 871-519 5430
E-mail: zhangyp@mail.kiz.ac.cn
Abstract
Background: Previous evidence has indicated that pigs were independently domesticated
in multiple places throughout the world. However, the detailed scenario of the origin and
dispersal of domestic pigs in East Asia remains unresolved.
Results: Population phylogenomic analysis was conducted in domestic pigs and wild
boars by screening the haplogroup specific mutation motifs inferred from a phylogenetic
tree of pig complete mtDNA sequences. All domestic pigs are clustered into a single
clade D (which contains sub-clades D1, D2, D3, and D4), with wild boars from East Asia
being interspersed. Three haplogroups within D1 are dominant in the Mekong region
(D1a2 and D1b) and the middle and downstream region of the Yangtze River (D1a1a),
and may represent independent founders of domestic pigs. None of the domestic pig
samples from Northeast Asia, the Yellow River region, and the upstream region of the
Yangtze River share the same haplogroup status with the local wild boars. The limited
regional distributions of haplogroups D1 (including its subhaplogroups), D2, D3, and D4
in domestic pigs suggest at least two different in situ domestication events.
Conclusion: The use of fine-grained mtDNA phylogenomic analysis of wild boars and
domestic pigs is a powerful tool to discern the origin of domestic pigs. Our results show
that pig domestication in East Asia mainly occurred in the Mekong region and the middle
and downstream region of the Yangtze River.