Dogs vary in size, shape, color, coat length and behavior more than any other animal and until now, this variance has largely been unexplained. Now, scientists have developed a method to identify the genetic basis for this diversity that may have far-reaching benefits for dogs and their owners.
In the cover story of tomorrow's edition of the science journal Genetics, research reveals locations in a dog's DNA that contain genes that scientists believe contribute to differences in body and skull shape, weight, fur color and length – and possibly even behavior, trainability and longevity.
"This exciting breakthrough, made possible by working with leaders in canine genetics, is helping us piece together the canine genome puzzle which will ultimately translate into potential benefit for dogs and their owners," said study co-author Paul G. Jones, PhD, a Mars Veterinary™ genetics researcher at the Waltham® Centre for Pet Nutrition – part of Mars® Incorporated, a world leader in pet care that has been studying canine genetic science for the past eight years. "By applying this research approach, we may be able to decipher how genes contribute to physical or behavioral traits that affect many breeds."
Dogs originally derived from the wolf more than 15,000 years ago – a blink of the eye in evolutionary terms. Selective breeding produced dogs with physical and behavioral traits that were well suited to the needs or desires of their human owners, such as herding or hunting ability, coat color and body and skull shape and size. This resulted in the massive variance seen among the more than 350 distinct breeds that make up today's dog population. Until now, the genetic drivers of this diversity have intrigued scientists who have been trying to explain how and why the difference in physical and behavioral traits in dogs changed so rapidly from its wolf origins.
An international team of researchers, which included scientists at the National Human Genome Research Institute, the University of Utah, Sundowners Kennels in Gilroy, California and Mars' Waltham Center for Pet Nutrition in the United Kingdom, studied simple genetic markers known as Single Nucleotide Polymorphisms, or SNPs, to find places in the dog genome that correlate with breed traits. Because many traits are "stereotyped" – or fixed within breeds – researchers can zero in on these "hot spots" to see what specific genes are in the area that might contribute to differences in traits.
No commentary. Just thought I'd flag it as interesting for everyone.
Just a quibble: last I heard, dogs weren't really derived from wolves at all, although they of course have a fairly recent (<100Ky) common ancestor. The claim is that they split off well before domestication.
ReplyDeleteAnyway, is there any reason to think that no extinct species could have been as diverse? Wouldn't such a species be logged as a dozen or more distinct species? Might there not be other extant but wild species of equal diversity, still logged as many distinct species?
Dogs hardly seem qualified bearers of a unique genetic capacity for diversity.
Just a quibble: last I heard, dogs weren't really derived from wolves at all, although they of course have a fairly recent (<100Ky) common ancestor. The claim is that they split off well before domestication.
ReplyDeleteInteresting. I hadn't heard this one. I have only heard that they were directly wolf derivs.
Anyway, is there any reason to think that no extinct species could have been as diverse? Wouldn't such a species be logged as a dozen or more distinct species?
ALmost assuredly. I wonder about Lystrosaurus.
Might there not be other extant but wild species of equal diversity, still logged as many distinct species?
Possible, but I doubt it. See below.
Dogs hardly seem qualified bearers of a unique genetic capacity for diversity.
Could be that its just the press release spin. However, they do seem to be the most polymorphic critter I can think of. They have been subjected to a very unique set of selective pressures. AFAIK, no other species has gone through that. The closest would be domestic cats and not nearly as much as been done to them as has been to dogs.
Just my opinion.