Evidence of three maternal lineages in near eastern sheep supporting multiple domestication events
Evidence of three maternal lineages in near eastern sheep supporting multiple domestication events
复制标题
DOI：
10.1098/rspb.2005.3204
复制
发表时间：
2005-10-22
影响因子：
4.7
通讯作者：
Bayón, Y
中科院分区：
文献类型：
--
作者：
Pedrosa, S;Uzun, M;Bayón, Y
对土耳其各地饲养的本地绵羊品种的线粒体DNA变异性进行了分析，对其D -环区域的一个片段和完整的细胞色素b进行了测序。分别对D -环和细胞色素b基因进行的系统发育分析显示出三个明显分离的聚类，表明存在三个主要的母系谱系，其中两个先前已被描述为B型和A型。新型C存在于所有分析的品种中，并显示出相当大的线粒体DNA变异性。根据细胞色素b基因得出分化时间，估计谱系B和A大约在16万 - 17万年前，而谱系C的分化被证明发生得更早（在45万到75万年前之间）。这些时间远远早于驯化时间，表明现代绵羊品种的起源比先前认为的更为复杂，并且至少发生了三次独立的绵羊驯化事件。我们的研究结果，连同考古信息以及近东地区现存的野生绵羊种群，都支持该地区在绵羊驯化过程中具有极其重要的地位。最后，第三个母系谱系的证据对现代绵羊的历史具有重要意义。
The variability of mtDNA was analysed in local sheep breeds reared throughout Turkey, for which a fragment of the D-loop region and the complete cytochrome b were sequenced. Phylogenctic analyses performed independently for the D-loop and the Cyt b gene revealed three clearly separated clusters indicating three major maternal lineages, two of which had been previously described as types B and A. The new type, C, was present in all the breeds analysed and showed considerable mtDNA variability. Divergence time was obtained on the basis of Cyt b gene and was estimated to be around 160 000-170 000 years ago for lineages B and A, whereas the divergence of lineage C proved to have occurred earlier (between 450 000 and 750 000 years ago). These times greatly predate domestication and suggest that the origin of modern sheep breeds was more complex than previously thought and that at least three independent sheep domestication events occurred. Our results, together with archaeological information and the current wild sheep populations in the Near East region support the high importance of this area in the sheep domestication process. Finally, the evidence of a third maternal lineage has important implications regarding the history of modern sheep.