United States – Shola, an English Shepherd Dog, was a member of the Edale Mountain Rescue Team as a young dog. This team of canines in the U.K. tended to injured and lost climbers.
New Solutions for Breeders
But Shola retired as part of the Rescue Team after she was diagnosed with a hereditary canine disease:
progressive retinal atrophy or PRA – which rendered her blind, as reported by HealthDay.
Shola has already been affected by this, but modern scientific development shows that there’s a gene test that could stop PRA from being transmitted to generations of puppies — perhaps someday, it could be eradicated from dog populations.
“Once the dog’s eyesight starts to fail, there’s no treatment – it will end up totally blind,” said Dr. Katherine Stanbury, the first author of the study who is a veterinary researcher from the University of Cambridge.
Sometimes, an owner may not know that their dog has PRA until they are middle-aged and long after the breeding process of puppies has taken place.
However, “now we have a DNA test, there’s no reason why another English Shepherd Dog ever needs to be born with this form of progressive retinal atrophy – it gives breeders a way of totally eliminating the disease,” Stanbury said in the same news release from Cambridge.
The challenge was in identifying which gene, or which genes, were responsible for the vision-eradicating condition.
Stanbury’s team achieved this by sequencing DNA samples of six English Shepherds affected by PRA and 20 healthy ones.
Identifying and Eliminating the Gene
The Cambridge group were already well placed for this kind of research because they provide a service which ensures that breeding does not result in puppies with genes that cause problems.
They were able to identify the gene responsible for PRA in English Shepherds almost instantly and followed that up with a profitable mouth swab test that alerts owners if their dog has the gene.
This gene is recessive, and as such, the breeding pair of male and female dogs must both possess it to pass the potential PRA trait to a puppy.
However, domestic dogs are much more inbred than outbred, so the probability of that happening is much higher, according to the Cambridge team.
However, “with the cost of a good bag of dog food, one can now get his or her English Shepherd checked for the PRA before breeding,” said the senior study author and Cambridge veterinary researcher, Dr Cathryn Mellersh.
‘It’s about prevention rather than a cure, and it means a huge amount to the people who breed these dogs,” she added. “They no longer need to worry about whether the puppies are going to be healthy or are going to develop this horrible disease in a few years’ time.”
Potential Implications for Human Health
The Cambridge group pointed out that PRA resembles an eye affliction known as retinitis pigmentosa, and therefore, developments made on this topic may shed light on vision impairment in people, as reported by HealthDay.
Regarding Shola, while she is no longer rescuing stuck hikers, her daughters are PRA-free and recently finished their schooling with Mountain Rescue Search Dogs England. However, “one of them saved a man’s life only three weeks ago,” the Cambridge news release stated.