摘要The aim of genetic monitoring is to checking the genetic contamination within inbred starains, which insures that the strains according with the require of colony . At present the methods based on allozyme biochemistry are the National Standard instructed. methods that using microsatellite DNA would be more useful for genetic monitoring than methods based on allozyme biochemistry because the genome itself is being tested rather than a protein product and a larger portion of the genome can be sampled, and easy to distinguish. methods that using microsatellite DNA had abundant microsatellite loci(over 7300, before 1999) can be identified. Applying enough microsatellite loci will present abundant straps and well polymorphism, which can reflection inherit and variation of roundly genene. In addition, this novel approach allows the rapid, sensitive, convenientand accuracy, even individual identificaton. So we should select microsatellite DNA which is polymorphisms as genetic monitoring markers to determining the strains' origin and genetic background of inbred mice.Untill now Only feasibility has been reported, and in which microsatellite DNA loci have not enough polymorphisms to distinguish genetic differences. Articles on standards and practicality have not been founded in our country. With the optimization of components of reaction buffer and amplificaton parameter, PCR for amplification microsatellite DNA was finally set up. Using the techniques microsatellite DNA can amplified efficaciously. The final concentrations of Mg2+ was 1 . 5-3.0 mmol/L, annealing temperature was 50 ℃-65 ℃. The condition for the PCR amplify were , 94 ℃ for 3min, 30cycles of 94℃ for 30s, 50℃-65℃ for 30s,72℃ for 1min,finally at 72℃ for 1min,then store at 4℃.