湖南等三地区东方田鼠遗传特性的分析比较

用染色体G带核型分析、生化位点、随机扩增多态性DNA(RAPD)标记等方法，对湖南洞庭湖湖滨、宁夏青铜峡市农田和黑龙江伊春市金山屯草甸3个地区的东方田鼠遗传特性进行了分析。结果表明，湖南和宁夏地区东方田鼠染色体数均为2N＝52，黑龙江东方田鼠染色体数则为2N＝42；生化位点结果显示3个地区的东方田鼠均呈遗传非均一性；湖南、宁夏和黑龙江鼠的个体间RAPD遗传距离分别为0．244（0．143—0．353)、0．226(0．161—0．294)、0．541(0.357—0．692)。湖南和宁夏两地区鼠种群间的遗传距离为0．367，湖南和宁夏鼠杂交一代与其亲代的RAPD遗传距离在0．310以下；但黑龙江鼠与湖南和宁夏鼠种群问的遗传距离分别为0．619和0．633。总的表明，3个地区的东方田鼠均呈遗传非均一性，但湖南与宁夏鼠在染色体、生化位点和RAPD标记等方面都具有相似性，并可杂交，而黑龙江鼠与其它两地的鼠不能杂交，且黑龙江鼠在遗传特性方面与前二地鼠有很大差异，因而后的“种”级分类地位值得进一步研究。

Analysis and Comparison of Hereditary Features of Field Vole ( Microtus fortis) from Three Different Regions

We use methods of chromosome G-band, biochemical markers, and RAPD markers of DNA to analyze hereditary features of Microtus fortis from a) lakesides of Dongting Lake, Hunan province; b) field of Qingtongxia county, Ningxia Hui Autonomous Region; and c) grassy marshland of Jinshantun, Yichun county, Heilongjiang province. Results indicate that the chromosome number of voles from Hunan and Ningxia is 2N = 52, while voles from Heilongjiang is 2N = 42. Results of biochemical sites indicate that the voles from these three regions are all non-even in heredity; the individual RAPD genetic distance of voles from Hunan, Ningxia and Heilongjiang is 0.244 (0.143-0.353), 0.226(0.161-0.294), 0.541(0.375-0.692)respectively. The RAPD genetic distance of voles from Hunan and Ningxia is 0.367, while the genetic distance of the first hybridized generation (Hunan and Ningxia) and their parents is under 0.310; but the genetic distance between voles from Heilongjiang and voles from Hunan and Ningxia is 0.619, 0.633 respectively. In brief, the voles from these three different regions are all non-even in heredity, but voles from Hunan and Ningxia are similar in chromosome numbers, biochemical sites, and genome RAPD markers. The voles from Ningxia and Hunan may hybrid, while the voles from Heilongjiang can't hybrid with the voles from the other two regions. The heredity of voles from Heilongjiang is quite different from voles of the other two regions, Thus its species position should be studied further.