DNA条形码鉴别内蒙古地区大沙鼠

目的探究应用DNA条形码技术对鼠疫宿主动物进行分子生物学鉴定的可行性。方法本研究检测了内蒙古布氏田鼠和长爪沙鼠鼠疫自然疫源地内形态上鉴定为8种啮齿动物的78条线粒体COI基因657bp的片段序列，经过双参数法计算遗传距离，采用邻接法（M）构建分析系统发育树。结果除大沙鼠外，种内平均遗传距离为0．6％，种间平均遗传距离为23．1％，而14只大沙鼠种内遗传距离高达8．1％，而分成2组后种内遗传距离最大为0．1％。NJ进化树能清楚的区分不同的鼠种。结论通过COI基因应用DNA条码技术可以对内蒙古的鼠疫宿主动物进行鉴别，同时认为乌兰察布长爪沙鼠疫源地的大沙鼠可能存在2个亚种。

Identification of Rhombomys opimus by DNA barcoding in Inner Mongolia area

Objective To study the feasibility of DNA bar - coding in the identification of molecular biology in host animals for plague. Methods This study tested the fragment sequences of the mitochondrial CO I 657bp from 78 specimens of 8 species rodents. For a region in the epidemic focus of Microtus Brandt and Mongolian gerbil in Inner Mongolia. The genetic distance was calculated through the method of double parameters, the phylogenetic trees were constructed with Neighbor- Joining （N J） method. Results The average intraspecific genetic distance （K2P） was 0.6% , the average intraspecific genetic distance is 23.1%, except the Rhombo- rays opimus, but the intraspccific genetic distance （K2P） was 8.1% between 14 Rhombomys opimus, while divided them into two groups, the highest intraspecific genetic distance was 0. 1%. A Neighbor -Joining tree could show clearly between different spices . Conclusions CO I sequencing of DNA bar - coding can be used to identify host animals for plague in Inner Mongolia, there might exist 2 species of Rhombomys opimus in the epidemic focus in Ulan Qab at the same time.