Chromosome markers in 12 inbred strains of the Norway rat, Rattus norvegicus.

Morphological details of metaphase chromosomes were compared among 12 inbred strains of rats (Rattus norvegicus) by means of conventional Giemsa staining and by a sequential Q- and C-banding method. Inter-strain variations were found in seven pairs, as identified on the basis of size differences in the short arms and/or satellites of chromosomes 3 and 12 and the X chromosome and in the centromeric C-bands of chromosomes 4, 5, 7, and 9. All pairs were homomorphic in the inbred strains, while F1 hybrids between two inbred strains showed certain heteromorphic pairs expected from the parents. These chromosome markers appear to be useful for characterization of inbred strains as well as for various genetic studies, including linkage analyses.