Introduction

This is a report showing that a disease similar to human Familial Adenomatous Polyposis Coli exists in a particular dog breed, the Jack Russell Terrier, and proves this disease is a familial inherited disease. In dogs affected, single to many polyps can be found from the stomach to the large intestines. In addition, it has been proven that an adenocarcinoma sequence occurs in the polyps over time.

Methods

Eight related Jack Russell terriers were evaluated in this study. All cases received the genetic test. The gene mutation that causes this disease is known to be an APC gene mutation in exon 4. The mutation is autosomal dominant.

Results

Six of eight JRTs were positive for the genetic mutation and the average age of positive for the test was 5.3 years. The symptoms of affected dogs included bloody stool, rectal excretion and vomiting occurring a while after eating. Affected dogs had hematological changes including low albumin, anemia, and elevated white blood cell count. Four of six JRTs positive for the mutation were found to have many adenocarcinoma lesions in the GI simultaneously. These dogs tended to live longer after diagnosed than typical gastric adenocarcinoma cases. NSAID’s are effective for this disease in the short term, but long-term use leads to gastric bleeding.

Conclusion

We believe that this disease exists not only in Japan but also in the world based on the analysis of patient’s pedigrees. A good understanding of this disease is important to reduce its incidence in this breed.