摘要 目的：对近3年北京地区的两个NIH封闭群小鼠群体的遗传质量进行监测分析。 方法：利用生化标记基因检测法，2011年测定A、B两单位NIH小鼠在碱性磷酸酶-1等14个遗传生化标记位点上的多态性。2014年利用相同方法原则对B单位的NIH小鼠群体进行抽样检测，比较了该小鼠群体3年来的遗传构成变化。结果：2011年，A、B两单位NIH小鼠群体均呈多态性的生化标记位点有6个（Ce2、Car2、Gpi1、Es10、Gpd1、Pgm1），且B单位在Es3位点也呈多态性；两群NIH小鼠在Car2位点有差异（P<0.05）,在Es3、Gpd1、Pgm1三个位点有显著差异（P<0.01）；两群体的群间分化系数为0.0406，遗传一致性指数为0.9619，遗传距离为0.0388。与2011年相比，B单位封闭群NIH小鼠在2014年出现了2个纯合位点（Ce2和Gpd1），同时Es10和Gpd1两位点差异极显著（P<0.01）,Pgm1位点差异显著（P<0.05）；不同代次NIH小鼠群间分化系数为0.1103，遗传一致性指数为0.8847，遗传距离为0.1266。结论：群体隔离、选种育种、种群数量和繁育代次等对NIH小鼠遗传构成差异影响显著。留种和繁育生产时应加强封闭群NIH小鼠的遗传监测，为其遗传质量的稳定性提供保障。

[Abstract]  Objective To analyse and monitor the genetic quality of closed colony NIH mice in Beijing district for the last 3 years.  Methods We use biochemical genetic markers(including alkaline phosphatase-1 and the like 14 biochemical markers), selecting A and B colonies from different facilities for genetic monitoring in 2011 to study the polymorphism. And in 2014, 30 NIH mice just from B colony were monitored using the same testing and sampling methods.  Results In 2011，NIH mice form both A and B facilities existed 6 polymorphic biochemical markers(Ce2,Car2,Gpi1,Es10,Gpd1,Pgm1) ; and NIH mice of B company also existed polymorphism in Es3 loucs. Between the 2 NIH mice colonies, there were significant difference in Es3、Gpd1、Pgm1 loci (P<0.01）, and difference in Car2 locus(P<0.05). FST of the 2 colonies was 0.0406, the genetic identity was 0.9619, and the genetic distance was 0.0388. In B company, NIH mice of 2014 appeared 2 homozygous loci(Ce2 and Gpd1) when compared with NIH mice of 2011. Between the 2 NIH mice colonies, there were significant difference in Es10 and Gpd1 loci (P<0.01）, and difference in Pgm1 locus(P<0.05). Fst of the 2 colonies was 0.1103, the genetic identity was 0.8847, and the Genetic distance was 0.1266.  Conclusions  Population isolation, breeding and selection, population quantity and generation significantly affected the genetic architecture of NIH mice. So when breeding and reserving seeds, we should strengthen the genetic monitoring of outbred NIH mice, in order to offer reliable genetic quality protection.