Association of Germ-line Polymorphisms in the Feline p53 Gene with Genetic Predisposition to Vaccine-Associated Feline Sarcoma

A case-control study was conducted in order to investigate the association of polymorphisms in the genomic sequence of the feline p53 gene with a predisposition to vaccine-associated feline sarcoma (VAFS). In the study, 50 domestic short hair cats with a confirmed histopathologic diagnosis of VAFS were matched to disease-free controls (1:2) by age, sex, and breed. Cats from both the diseased (case) and control groups were also negative for feline leukemia virus and feline immunodeficiency virus. Germ-line DNA was prepared from blood samples from cats in both groups and analyzed for sequence variation at 8 polymorphic sites in the p53 gene. A strong association was found between VAFS and the presence of specific nucleotides at 2 of the polymorphic sites. The strongest association was observed for a single-base insertion in intron 7 of the gene with an odds ratio of 8.99 (95% confidence interval = 3.42-23.57, P < 0.0001). The results of the study indicate that analysis of the presence or absence of the identified genetic markers in apparently healthy disease-free cats may help in predicting which individual animals are at greater risk of developing the disease.