Study Finds These 3 Dog Breeds Are Most At Risk For Cancer

The dogs are called man’s best friend for good reason, sticking with us for thousands of years.

But according to new research, they could not only be valuable companions – they could also potentially save our lives from dangerous illnesses.

What’s up – Supported by a team of French researchers, a study published Thursday in the journal PLOS Genetics identifies genetic risk factors associated with histiocytic sarcoma, a rare blood cancer that occurs in humans and dogs.

This study focused on three dog breeds, which share similar loci that occur in several canine cancers. Dogs include Bernese Mountain Dogs, Rottweilers, and Retrievers – specifically, Flat Coated Retrievers and Golden Retrievers.

From their research, the scientists had a few takeaways:

• a previously identified locus, or the specific location of a gene on a chromosome, known as CDKN2A is associated with an increased risk of histiocytic sarcoma
• scientists have also identified new loci associated with a risk of histiocytic sarcoma on canine chromosomes 2, 5, 14 and 20
• researchers concluded that these loci pose additional risks for other cancers, such as lymphoma or mast cells

The latest finding may also have special implications for the study of histiocytic sarcoma in humans

In a press release, the study’s authors write: “This study took advantage of canine breed predispositions to decipher the genetic basis of histiocytic sarcoma, a rare human cancer.”

How they did it – The researchers looked at the shared genetic risk of histiocytic sarcoma among the three dog breeds, also known as the genome-wide association study.

Scientists are using these studies to look for markers of disease in the DNA of different people – or different breeds of dogs, in this case – to help treat and prevent the disease. In this case, the researchers also used targeted genetic sequencing of specific loci to identify genetic variants linked to cancer.

The authors write in the study: “This study aimed to extend previous studies by deciphering the genetic basis of (histiocytic sarcoma) using a multi-breed approach.”

This is the largest genome-wide association study on the risk of histiocytic sarcoma in dogs.

Dig into the details – Researchers have confirmed several risky alleles associated with a higher risk of histiocytic sarcoma.

Researchers found that individual dogs of breeds that inherited at least 5 out of 6 of these risk alleles at three specific loci – CFA11, CFA5, and CFA14 – were five times more likely to develop histiocytic sarcoma.

Why is this important – The specific alleles located in the three dog breeds correlate not only with a higher risk of blood cancer, but also with lymphoma and other types of cancer.

This additive effect is known as pleiotropy, which occurs when a gene can unexpectedly have multiple effects.

Pleiotropy is also a common occurrence in human cancer research, which makes the study relevant for the study of histiocytic sarcoma in humans as well.

The researchers write that the sheer genetic diversity of human cancers makes studying their underlying genetic predisposition “almost impossible in rare cancers” like histiocytic sarcoma.

However, dogs have been bred artificially in a way that makes it easier to identify the gene expression of certain alleles that carry a higher risk of cancer. So if we can identify these genetic risk factors in dogs, it could be the first step in identifying and treating them in humans as well.

The researchers conclude that research on these three dog breeds “offers a unique opportunity to unravel the genetic basis of this cancer.”

And after – The research promises exciting possibilities – not only for potentially treating these three dog breeds for blood cancer, but also for humans.

As the researchers write: “Thus, spontaneously affected companion dogs with breed-specific cancers provide effective natural models for identifying underlying genetics. several homologous dog-human cancers. “

However, scientists still have a long way to go before they can fully unlock the common mechanisms underlying blood cancer in these three dog breeds.

For example, the study contains a limited sample of flat-coated retrievers, so future research will need to focus more on the retriever’s genetic similarities to the other two dog breeds studied.

Research also identifies alleles that are strongly correlated with several types of cancer in golden retrievers. But more research is needed to determine whether Bernese Mountain Dogs also share these same risky cancer alleles.

Yet, for now, we can take comfort in the idea that humans share more in common with our favorite dogs than previously thought – and that this similarity may just save us from future cancers.

Abstract: Histiocytic sarcoma (HS) is a rare but aggressive cancer in humans and dogs. The spontaneous canine model, which shows clinical, epidemiological and histological similarities to human HS and specific breed predispositions, offers a unique opportunity to unravel the genetic basis of this cancer. In this study, we sought to identify germline risk factors associated with the development of HS in breeds with canine predisposition. We used a methodology that combined multiple genome-wide association studies in a multi-breed, multi-cancer approach as well as targeted next-generation sequencing and imputation. We combined multiple dog breeds (Cattle Dog Bernese, Rottweilers, Flat-Coated Retrievers, and Golden Retrievers) and three hematopoietic cancers (HS, lymphoma and mast cell tumor). The results showed that we not only refined the previously identified HS risk CDKN2A locus, but also identified new loci on canine chromosomes 2, 5, 14 and 20. The capture and targeted sequencing of specific loci suggested the existence of regulatory variants in non-coding regions. and methylation mechanisms linked to risk haplotypes, which lead to a strong predisposition to cancer in certain breeds of dogs. We have also shown that these canine cancer predisposing loci appear to be due to the additive effect of several risk haplotypes involved in other hematopoietic cancers such as lymphoma or mast cell tumors. This illustrates the pleiotropic nature of these canine cancer loci as observed in human oncology, thus enhancing the interest of dog breeds predisposed to study cancer initiation and progression.