Analysis of the Giemsa-banding patterns of the chromosomes from rats carrying the genes of the growth and reproduction complex (GRC).

Morphological studies of metaphase chromosomes were done with rats derived from the BIL/1 strain, which has genes affecting growth and reproduction linked to the major histocompatibility complex by conventional Giemsa-trypsin staining and the results were compared to rat strains not carrying these defects. A subterminal-terminal centromeric polymorphism was detected in chromosome 3 [del 3 (pter leads to cent)] among the strains studied. Comparison of the G-banded karotypes of the rats carrying the defects with the karotypes of the other strains did not reveal any gross chromosomal abnormalities.