Genetic marker patterns and endogenous mammary tumor virus genes in inbred mouse strains of Japan.

In order to establish the genetic relatedness of the inbred mouse strains kept in Nara, genetic marker patterns were determined in conjunction with a study on endogenous mammary tumor viral genes in these strains. Isoenzyme patterns combined with patterns of other genetic markers, show that the unrelatedness between various inbred strains of the dd stock is as high or even higher as between strains of known different origin and geneology. Based on endogenous viral gene patterns the dd stock derived mice can be subdivided into three group, DDD, DDN, DDO, KF and DD/Tbr. The DD/Tbr and its foster-nursed substrain (DD/Tbrf) have the lowest number of endogenous viral genes, i.e. two, while the other strains carry 4-6 such genes. The SLN and SHN strains, derived from a Swiss stock, have a similar pattern of viral genes different that of all other strains studied, also strains of Swiss origin from other sources, such as the NFS and the GR.