National Beagle Council (Australia)

Catalase deficiency, also known as acatalasemia, is a rare but important genetic condition that can affect beagles and other dog breeds. Catalase is an enzyme that plays a crucial role in protecting cells from damage by breaking down hydrogen peroxide—a harmful byproduct of metabolism—into water and oxygen. When a beagle has catalase deficiency, its body can’t efficiently perform this protective process, which may lead to health problems.

In beagles, catalase deficiency is usually inherited as an autosomal recessive trait. This means a dog must receive the defective gene from both parents to show signs of the disease. Dogs that inherit only one copy of the gene typically don’t show symptoms but can pass the gene on to their offspring.

While many dogs with catalase deficiency can live fairly normal lives, some may develop problems, especially in tissues and organs regularly exposed to hydrogen peroxide. One of the most common issues reported is oral ulcers—painful sores inside the mouth that can make eating uncomfortable. In rare cases, the deficiency might contribute to inflammation or other complications in organs like the liver.

Veterinary diagnosis often starts with noticing recurring oral ulcers or other unexplained tissue damage. A vet can confirm catalase deficiency with enzyme activity tests or genetic testing. Although there’s currently no cure, managing the condition usually involves treating symptoms, such as keeping oral ulcers clean and reducing sources of oxidative stress.

For beagle breeders and owners, awareness of catalase deficiency is important. Responsible breeding practices, including genetic testing, can help reduce the risk of passing this condition on to future generations. While catalase deficiency isn’t among the most common health issues in beagles, it serves as a reminder of why genetics matter in maintaining the health and happiness of our four-legged companions.

References

Nakamura, K., Watanabe, M., Takanaka, K., Sasaki, Y., Ikeda, T. : cDNA cloning of mutant catalase in acatalasemic beagle dog: single nucleotide substitution leading to thermal-instability and enhanced proteolysis of mutant enzyme International Journal of Biochemistry & Cell Biology 32:1183-1193, 2000. National Library of Medicine 2000 Nov-Dec

Purification and characterization of liver catalase in acatalasemic beagle dog: comparison with normal dog liver catalase.Nakamura K, Watanabe M, Sasaki Y, Ikeda T.Int J Biochem Cell Biol. 2000 Jan;32(1):89-98. doi: 10.1016/s1357-2725(99)00110-7.PMID: 10661897