Can old dogs teach us new longevity tricks?

Golden retrievers are one of the most popular breeds of dogs – in fact, there are approximately 78 million of them worldwide [1]. However, while they are a popular pet, they have up to a 65% chance of dying from cancer [2].

Researchers from University of California, Davis set out to find if certain genetic factors affected the dogs survival rate; rather than looking for genes associated with cancer in the breed, however, they instead focused on searching for genes associated with longer lifespan.

Longevity.Technology: The gene they discovered is in a family of proteins that have long known to be important in human cancers, and specific versions or variants of the gene were associated with an increased lifespan of nearly two years [3]. The results of the study have been published in GeroScience.

“We assume that the majority of golden retrievers have a genetic predisposition to cancer, but if some of them are living to be 14, 15 or 16, we thought there could be another genetic factor that is helping to mitigate the bad genes, and the gene that popped out for us is HER4,” said co-corresponding author Robert Rebhun, Maxine Adler Endowed Chair in oncology at the UC Davis School of Veterinary Medicine [4].

HER4, also known as ERBB4, is a member of the family of human epidermal growth factor receptors. It is also in the same family of genes in humans as HER2 – a gene well-known for causing rapid growth of cancer cells. Rebhun explained that many cancers that dogs develop are the same as cancers in humans, so this discovery could be of significance both for oncology and geroscience.

“If we find that this variant in HER4 is important either in the formation or progression of cancer in golden retrievers, or if it can actually modify a cancer risk in this cancer predisposed population, that may be something that can be used in future cancer studies in humans,” he said [4].

Golden years

The researchers studied more than 300 golden retrievers in the study, comparing DNA from blood samples of dogs that were alive at 14 years of age with those that died before age 12. They found that dogs with certain variants of the gene survived longer – on average 13.5 years compared with 11.6 years [3].  

“Almost two years is a significant difference in a dog’s life,” said co-corresponding author Danika Bannasch, Maxine Adler Endowed Chair in genetics with the UC Davis School of Veterinary Medicine. “Wouldn’t we all want our beloved pets to live another two years? Two years in goldens is about a 15-20% increase in lifespan, the equivalent of 12-14 years in humans [4].”

Of course cancer is a complicated puzzle, and while this study has only identified a small piece, Bannasch said that although there are going to be many genes involved in the development of a cancer in a golden retriever, finding one with longevity implications is significant.

“The fact that the gene associated with longevity is also a gene involved in cancer was really interesting to us,” she said [4].

The study also found the gene variant seemed to be most important to the longevity of female dogs compared with male dogs. HER4 has been shown to interact with hormones such as estrogen and may also play a role in processing environmental toxins.

The researchers now want to enroll a larger population of golden retrievers in a study to see if they can reproduce these results; this would hopefully allow them to discover how this genetic variant may impact expression or function of the gene.