Although by now most people accept that dogs and wolves are closely related genetically, a question still remains about which breeds are most related to wolves and to other breeds. A recent study published in Nature magazine (vonHoldt, B. M. et al. 2010, Genome-wide SNP and haplotype analyses reveal a rich history underlying dog domestication, Nature 464 (8 April 2010): 898-903 DOI: 10.1038/nature08837) has examined this question.
The experimenters used a technique called Single Nucleotide Polymorphisms(SNPs) to study the genetic relationships among samples from 912 dogs representing 85 breeds, as well as samples from 225 grey wolves from 11 different geographic areas around the world.
I was surprised to see that wolves from the Middle East contributed a significant portion of genetic variation to most of the modern dog breeds. Of the dog breeds that were examined, the Basenji had the highest genetic relatedness to Middle Eastern wolves. Other breeds that were more closely related to wolves included the Akita, Chow Chow, Dingo, Shar-Pei, Alaskan Malamute, Siberian Husky, Afghan Hound, Saluki, American Eskimo, and Samoyed.
Breeds that had higher genetic relatedness with European wolves included Greyhounds, Whippets, Miniature Pinschers, and Staffordshire Bull Terriers. The Akita and Chow Chow had higher relatedness with Chinese wolves, as might be expected.
Also as could be expected, Old World wolves had higher genetic relatedness to dog breeds than New World wolves, suggesting that domestication of dogs took place in Europe, the Middle East, or Asia, rather than in North America.
Some of the genetic relationships between the breeds surprised me. For example:
· the Chihuahua was relatively closely related genetically to the Pomeranian and the American Eskimo,
· the Papillon was relatively closely related to the Pug, Brussels Griffon, Shih-tzu, and Pekinese,
· the Portugese Water Dog was relatively closely related to the German Shepherd, Standard Schnauzer, Giant Schnauzer, and Doberman Pincher
· the Newfoundland was closely related to the Labrador, Flat-Coated Retriever and Golden Retriever,
· the Rhodesian Ridgeback was relatively closely related to the Great Dane and Rottweiler.
These relationships suggest that our conventional categories of dogs (e.g., Working Dogs, Herding Dogs, etc.) are groupings that we make for our convenience, rather than groupings that reflect the relatedness of the different breeds.
One thing, however, does not surprise me: We humans are pretty good at coming up with different breeds of dogs.