Amplification of the major satellite DNA family (FA-SAT) in a cat fibrosarcoma might be related to chromosomal instability.
Most mammalian chromosomes have satellite DNA sequences located at or near the centromeres, organized in arrays of variable size and higher order structure. The implications of these specific repetitive DNA sequences and their organization for centromere function are still quite cloudy. In contrast to most mammalian species, the domestic cat seems to have the major satellite DNA family (FA-SAT) localized primarily at the telomeres and secondarily at the centromeres of the chromosomes. In the present work, we analyzed chromosome preparations from a fibrosarcoma, in comparison with nontumor cells (epithelial tissue) from the same individual, by in situ hybridization of the FA-SAT cat satellite DNA family. This repetitive sequence was found to be amplified in the cat tumor chromosomes analyzed. The amplification of these satellite DNA sequences in the cat chromosomes with variable number and appearance (marker chromosomes) is discussed and might be related to mitotic instability, which could explain the exhibition of complex patterns of chromosome aberrations detected in the fibrosarcoma analyzed.
Department of Genetics and Biotechnology, Centre of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro, P-5001-801 Vila Real, Portugal.
Sara
S
Santos
Raquel
R
Chaves
Filomena
F
Adega
Estela
E
Bastos
Henrique
H
Guedes-Pinto
D000818:Animals; D002415:Cats; D002869:Chromosome Aberrations / Q000662:veterinary*; D002871:Chromosome Banding / Q000662:veterinary; D004276:DNA, Satellite / Q000235:genetics*; D005260:Female; D005354:Fibrosarcoma / Q000235:genetics / Q000662:veterinary*; D005784:Gene Amplification / Q000502:physiology*; D017404:In Situ Hybridization, Fluorescence / Q000662:veterinary
D004276:DNA, Satellite