ABSTRACT
A cell line derived from a spleen metastasis of a mammary carcinoma in a female dog was analyzed by fluorescence in situ hybridization with canine chromosome-specific paints. The cell line showed a modal chromosome number of 77, with three (90% of the cells) or four (10% of the cells) biarmed chromosomes. Aberrations observed relate to chromosomes 8 or 11, 13 or 15, 37, 38, and X and include chromosome loss (X), formation of isochromosomes (8 or 11, 13 or 15), and centric fusion (37 and 38). In all aberrations, whole chromosomes are involved. None of the genes known to be related to breast cancer development in humans and that has mapped in the dog is located on one of the aberrant chromosomes. The results of this study show that chromosome painting is a most useful tool for the analysis of canine tumor cells.
