UC Davis researchers have performed a genome-wide association study to identify genetic variants in golden retrievers that could affect the cancer-predisposed breed’s longevity.
“We assume that the majority of golden retrievers have a genetic predisposition to cancer, but if some of them are living to be 14 or older, we thought there could be another genetic factor helping to mitigate the bad genes,” said co-corresponding author Dr. Robert Rebhun, the Maxine Adler Endowed Chair in oncology at the University of California, Davis, School of Veterinary Medicine.
Researchers looked at the DNA of more than 300 golden retrievers and compared the dogs alive at 14 years old with those that died before age 12. They found that dogs with certain variants of the gene ERBB4, also known as HER4, survived an average of 13.5 years, compared with 11.6 years for the others.
“Almost two years is a significant difference in a dog’s life,” said co-corresponding author Dr. Danika Bannasch, the veterinary school’s Maxine Adler Endowed Chair in genetics. “Two years in goldens is about a 15% to 20% increase in lifespan, the equivalent of 12 to 14 years in humans.”
ERBB4 is a member of the human epidermal growth factor receptor family and can function as an oncogene or a tumor suppressor gene.
“The fact that the gene associated with longevity is also a gene involved in cancer was really interesting to us,” Dr. Bannach said.
HER4 has been shown to interact with hormones such as estrogen, which might explain the study’s finding that the gene variant seemed most important to the female dogs’ longevity.
The discovery could have ramifications in human medicine.
“If we find this variant in HER4 is important in the formation or progression of cancer in golden retrievers, or if it can modify a cancer risk in this cancer-predisposed population, that may be something that can be used in future cancer studies in humans,” Dr. Rebhun said.
The researchers plan to study a larger golden retriever population to see whether they can reproduce the results and determine how the variant might influence gene expression or function. They also plan to evaluate HER4 variants in other breeds, canine tumors and other species.