Heredity of animal cancer

Last Modified: April 11, 2003


Dear OncoLink "Ask The Experts,"
I lost my dog to cancer. I would like to get another dog from the same breeder. I am unsure how much of a role genetics plays into the likelihood that a dog will develop cancer. I know there is no guarantee of a completely healthy dog (regardless of the breed) but I also do not want to set myself up for another loss if there is a great chance of a related dog developing the same disease. Any advice you can give to help me assess the situation would be most appreciated.  


Lili Duda, VMD, Section Editor of the OncoLink Veterinary Oncology Menu, responds:

This is a very difficult question to answer. Dog and cat breeds, by definition, are highly inbred which increases the chances of a variety of recessive traits being manifested in any given breed. It is well known that every breed has diseases to which they are more susceptible than the average dog, and in some breeds this susceptibility can be quite pronounced such that a large percentage of animals will be either carriers or affected with a given trait, condition, or disease. There are definitely breeds, which are more susceptible to a variety of cancers. However, cancer is a multifactorial disease that results from a complex interaction of genetics, environment, life history, etc. It is always helpful to ask a breeder for the medical history of the lineage of the puppy you are considering, as well as for references of other owners that have purchased puppies from the same breeder. You can also ask for information from the organizational body that oversees the particular breed's registration, judging criteria, etc.