Applying canine research findings to humans
As a result, each breed of dog has a clearly distinguishable genetic landscape with a high degree of genetic similarity within breeds and large differences between breeds. This makes it easier to identify causal gene variations for specific illnesses.
“Because the genetic variation is so low within dog breeds, it is faster and easier to find each individual gene responsible for a disease than it is in humans,” Dr. Bergström said.
Once a disease-causing gene has been discovered and linked to a specific disease in dogs, scientists can assess whether the same gene may be of importance for similar conditions in humans.
Whole-genome sequencing speeds up lab research
Back in the brightly-lit laboratory in Sweden, the pace of SLU’s research has increased exponentially in recent years thanks to the plummeting cost of whole-genome sequencing.
The team initially identified mutated genes in dogs using the traditional method of collecting 20 control samples and 20 cases, then comparing them in a laborious process of genome-wide association analysis that could take up to one year.
Today, the same stage can be reached within weeks using whole genome sequencing. This enables Dr. Bergström and his team to identify the mutated gene that is underlying a specific inherited disease much more quickly by comparing the same genes within a dog family, where the parents are healthy but the offspring suffer a disease. Once the gene mutation has been discovered in the sufferer, the hard work begins.
“Our first goal is to find the mutation. Our second goal is to understand what that mutation does. What is the biology of the disease? What protein does it interact with? Once you know that, you can start thinking about therapies,” Dr. Bergström said.
The SLU’s findings are already helping dog breeders to make educated decisions on how to choose parents for the next generation of puppies.
The new ‘Nordic Canine Genome Project’ will reveal further vital information about canine health. Launched this spring, the three-year project aims to get complete genome sequences of 100 dogs of which about 30 breeds are native to the Nordic countries of Iceland, Denmark, Norway, Finland and Sweden.
The project, sponsored by the Swedish Kennel Club and insurance company AGRIA, will shed light on which genetic variations are the norm within each dog breed – and which are likely to cause inherited diseases among those breeds.
When it comes to human health, identifying the mutated gene responsible for inherited eye diseases and other conditions in dogs is just the first step towards reducing the frequency of the mutation within the dog breed – and allowing development of effective treatments for canine and human patients.
The next step – and the most difficult one – is to identify and understand the biology of each of the mutations and exactly how they cause diseases. "In future, understanding the underlying biological processes that cause diseases will be the most important part of this work,” Dr. Bergström explains.
“The real challenge for modern biology is to define what’s needed to invent therapies and pharmaceuticals for successful treatment of diseases.”
The Department of Animal Breeding and Genetics belongs to the Faculty of Veterinary Medicine and Animal Science at the Swedish University of Agricultural Sciences (SLU) in Uppsala. The department conducts research on domestic animals in the fields of molecular genetics and bioinformatics as well as quantitative and applied genetics. Its Canine Biobank, developed in collaboration between SLU and Uppsala University, is intended to increase knowledge of the biology of genetic diseases occurring in both dogs and humans. The research aims to improve canine and human health and support veterinary and human medicine. The laboratory also offers genetic services for animals such as parental control or testing for inherited diseases. http://bit.ly/SLUGenetics.