A Dog’s Screw Tail May Give Insight To A Rare Human Syndrome
One of the most adorable things about bulldogs, French Bulldogs and Boston Terriers is their well-known short, kinked tail. (Along with their big, wide-eyes and those charming stubby little faces, of course!) Known as ‘screw tails,’ they are unique to those breeds, according to Professor Danika Bannasch. She is with the Department of Population Health and Reproduction in the UC Davis School of Veterinary Medicine and says that those three breeds don’t have the vertebrae that make up a tailbone.
Now researchers at UC Davis have sequenced an entire DNA sequence from 100 dogs, 10 of which came from ‘screw tail’ breeds. They found that the genetic basis for the tail and have linked it to a rare syndrome in humans. They looked at over 12 million individual differences in the sequence and found one mutation in a gene known as DISHEVELLED 2, or DVL2. In 100% of the Bulldogs and French Bulldogs sampled, this variant was found, and it was also very common in Boston terriers as well.
Professor Henry Ho studies similar genes in humans at the UC Davis School of Medicine. The mutations found in related DVL1 and DVL3 genes are associated with Robinow syndrome, which is a rare inherited disorder in humans. The disorder causes very similar changes in the anatomy of humans–short/wide ‘babyfaces’ with shorter limbs and spinal deformities. As well, those with Robinow syndrome have cleft palates traits, just as do ‘screw tail’ breeds. Using the characterization of the screw tail DVL2 protein product, the researchers believed there to be a common molecular defect that was responsible for the very distinct and similar appearances in both screw tail dog breeds and patients with Robinow.
While the findings don’t necessarily mean much concerning dogs in that the DVL2 screw tail mutation is so closely associated with the breed appearance and difficult to ‘breed out,’ it may be a model for research for the human syndrome, Dr. Bannasch says. Because it’s so common in several popular dog breeds, but so rare in humans, the information can lead the way to finding more about the effects and ways to battle in humans. Only several hundred cases of Robinow have been documented since its initial identification in 1969.
One more case of dogs helping their humans however they can.
More by Lori Ennis