Prager E M, Orrego C, Sage R D
Division of Biochemistry and Molecular Biology, University of California, Berkeley, California 94720-3202, USA.
Genetics. 1998 Oct;150(2):835-61. doi: 10.1093/genetics/150.2.835.
The mitochondrial DNA (mtDNA) control region and flanking tRNAs were sequenced from 76 mice collected at 60 localities extending from Egypt through Turkey, Yemen, Iran, Afghanistan, Pakistan, and Nepal to eastern Asia. Segments of the Y chromosome and of a processed p53 pseudogene (Psip53) were amplified from many of these mice and from others collected elsewhere in Eurasia and North Africa. The 251 mtDNA types, including 54 new ones reported here, now identified from commensal house mice (Mus musculus group) by sequencing this segment can be organized into four major lineages-domesticus, musculus, castaneus, and a new lineage found in Yemen. Evolutionary tree analysis suggested the domesticus mtDNAs as the sister group to the other three commensal mtDNA lineages and the Yemeni mtDNAs as the next oldest lineage. Using this tree and the phylogeographic approach, we derived a new model for the origin and radiation of commensal house mice whose main features are an origin in west-central Asia (within the present-day range of M. domesticus) and the sequential spreading of mice first to the southern Arabian Peninsula, thence eastward and northward into south-central Asia, and later from south-central Asia to north-central Asia (and thence into most of northern Eurasia) and to southeastern Asia. Y chromosomes with and without an 18-bp deletion in the Zfy-2 gene were detected among mice from Iran and Afghanistan, while only undeleted Ys were found in Turkey, Yemen, Pakistan, and Nepal. Polymorphism for the presence of a Psip53 was observed in Georgia, Iran, Turkmenistan, Afghanistan, and Pakistan. Sequencing of a 128-bp Psip53 segment from 79 commensal mice revealed 12 variable sites and implicated >/=14 alleles. The allele that appeared to be phylogenetically ancestral was widespread, and the greatest diversity was observed in Turkey, Afghanistan, Pakistan, and Nepal. Two mice provided evidence for a second Psip53 locus in some commensal populations.
对从埃及延伸至土耳其、也门、伊朗、阿富汗、巴基斯坦、尼泊尔直至东亚的60个地点采集的76只小鼠的线粒体DNA(mtDNA)控制区及侧翼tRNA进行了测序。从其中许多小鼠以及在欧亚大陆其他地区和北非采集的其他小鼠中扩增出Y染色体片段和一个加工过的p53假基因(Psip53)片段。通过对该片段进行测序,目前从家栖小鼠(小家鼠组)中鉴定出251种mtDNA类型,包括本文报道的54种新类型,这些类型可分为四个主要谱系——家鼠谱系、小家鼠谱系、栗色鼠谱系以及在也门发现的一个新谱系。进化树分析表明,家鼠谱系的mtDNA是其他三个家栖mtDNA谱系的姐妹群,而也门的mtDNA是次古老的谱系。利用这棵树和系统地理学方法,我们得出了一个关于家栖小鼠起源和扩散的新模型,其主要特征是起源于中亚中西部(在当今家鼠的分布范围内),小鼠首先依次扩散到阿拉伯半岛南部,然后向东和向北进入中亚中部,后来从中亚中部扩散到中亚北部(并由此进入欧亚大陆北部的大部分地区)以及东南亚。在来自伊朗和阿富汗的小鼠中检测到Zfy - 2基因中有18 bp缺失和无缺失的Y染色体,而在土耳其、也门、巴基斯坦和尼泊尔只发现了无缺失的Y染色体。在格鲁吉亚、伊朗、土库曼斯坦、阿富汗和巴基斯坦观察到Psip53存在的多态性。对79只家栖小鼠的128 bp Psip53片段进行测序,发现了12个可变位点,并涉及≥14个等位基因。在系统发育上似乎是祖先型的等位基因分布广泛,在土耳其、阿富汗、巴基斯坦和尼泊尔观察到了最大的多样性。两只小鼠为某些家栖种群中存在第二个Psip53位点提供了证据。