Sino-Japnese cooperative studies on the genetic differentiation of Wild mice and rice.

自1983年以来，我们对西藏南部的中国、蒙古国和东北的中国北部、兰州以西的西部中国等地的野生鼠种群进行了15次遗传变异调查。对家鼠线粒体DNA、核糖体DNA、Y染色体SRY DNA、血红蛋白-β(Hbb)等遗传多态性的分子分析表明，家鼠存在两个主要的亚种群，即卡氏小鼠群和肌肉小鼠群。前者在长江以南，后者在长江以北，包括东北、朝鲜半岛和日本。更详细的分析表明，亚种群进一步分化。在肌肉亚种群中，根据形态被划分为甘肃亚种的西部种群可以被描述为一个新的Hbbw1。中心种群为Hbb-p亚种，东北种群包括朝鲜和日本，Molossinus亚种为…更多的种，被它们特有的SRYmo分开。线粒体DNA的D-loop分析可明显区分南方中国种群和东南亚种群。应该注意的是，日本北部的种群表现为后一种类型的mt-DNA，这可能与我国历史上人类从东南亚向日本的迁移有关。东乡野生稻是普通野生稻的最北端种群。这些植物是多年生植物，它们能在严寒的冬季存活下来，表现出高度的耐寒性。通过在江西大学实验场进行的杂交和选择，成功地将低温抗性转移到栽培稻中。尽管所有品种都没有越冬，但所选的植株都能存活过冬。核糖体DNA在野生稻和栽培稻中高度多态。桐乡野生稻携带的rDNA结构在粳型水稻中占优势，但在热带亚洲国家的野生稻中没有发现这种重复序列。用原位杂交(FISH)方法检测rDNA重复序列的位置。发现了与携带rDNA簇的染色体数量和染色体位置有关的变异。这一发现支持了之前的假设，即野生稻显示出高水平的遗传多样性，其潜力可能与亚洲栽培稻的多样化有关。较少

Since 1983, we have surveye15d the genetic variations among the wild mouse populations in southern China including Tibet, northern China including Mongol and the Northeast, and western China far west of Lanzhou. Molecular analyzes of the genetic polymorphisms in mitochondrial DNAs, ribosomal DNAs, Y-chromosome SRY DNAs, hemoglobin-beta(Hbb)and others, revealed the presence of two major subspecies groups in the house mouse, Mus musculus, which are castaneus group and musculus group. The former habits south of Yangtze river and the latter north of it including the Northeast, Korean peninsula and Japan. More detailed analyzes demonstrated the further differentiation of the subspecies groups. In the musculus subspecies group, western populations which were classified gansuensis subspecies based on the morphology could be characterized by a new Hbbw1. Central populations, homourus subspecies, were characterized by Hbb-p and northeastern populations including Korea and Japan, molossinus subs … More pecies, were separated by their characteristic SRYmo. In the castaneus subspecies group, southern China population and southeast Asian population were clearly discriminated by the D-loop analysis in mitochondrial DNAs. It should be noted that the northern Japanese populations show the latter type mt-DNA.This is probably related to the human movement from southeast Asia to Japan in our history.Dongxiang wild rice is the northernmost population of a common wild rice. The plants are of perennial and they survive beyond severe winter seasons showing a high degree of lowtemperature-resistance. By means of hybridization and selection carried out at an experimental farm of Jiangxi University, The resistance to low temperatures were successfully transferred into cultivated rice. The selected plants survived beyond winter in spite that none of cultivars survived beyond winter. Ribosomal DNA is highly polymorphic among wild and cultivated rice. Tongxiang wild rice carries rDNA structurse which are predominant in Japonica type of rice, although such repeats were not found in wild rice from tropical Asian countries. The location of rDNA repeats were examined by means of in situ hybridization (FISH) method. Variations were found in relation to the number of chromosomes carrying an rDNA cluster as well as chromosomal location. This finding supports the previous assumption that wild rice shows a high level of genetic diversity and its potentiality might be related to diversification of cultivated rice in Asia. Less