Mutated Gene

Researchers Study Mutated Gene.
By Randolf E. Schmid
Associated Press Writer
WASHINGTON


Researchers studying a single mutated gene in Collies have discovered that breed's family tree includes not only several herding dogs, but a couple of sight hounds as well, tracing back to a single animal that lived in England prior to the 1870s.

Collies, traditional herders but also one of the most popular breed of dogs, can suffer a potentially fatal reaction to 20 commonly used drugs. The affected dogs have a single mutated gene called MDR1 that makes them susceptible to drugs ranging from antibiotics to cancer drugs, steroids and heart medications.

A team of researchers led by Mark W. Neff of the University of California, Davis, studied 4,000 samples from purebred dogs and discovered the mutated gene in several other breeds as well as Collies, suggesting some previously unexpected family relationships. Just over half of tested Collies 54.6 percent had the mutated gene, the team reports in this week's issue of Proceedings of the National Academy of Sciences.

But it also turned up in 41.6 percent of Longhaired Whippets, 25.9 percent of miniature Australian Shepherds, 17.9 percent of Silken Windhounds and smaller percentages of Australian Shepherds, English Sheepdogs, McNabs, Old English Sheepdogs and Shetland Sheepdogs.

Before the time of dog shows and strictly controlled breeding to keep breeds separate, dogs tended to exist in regional varieties depending on terrain and working style. Many traditional varieties began to be neglected in the late 1800s, and dog shows and breed registries were established to preserve the various dogs, with the Collie, Old English Sheepdog and Shetland Sheepdog among the first, the researchers say. They suggest that the several herding dogs with the mutated gene probably shared it before the time of formal breeds, when sheep owners tended to use a variety of dogs to tend their flocks.

Tracing the gene to the Longhaired Whippet and Silken Windhound, both hounds that hunt by sight, is another story, the scientists report.

The Silken Windhound was developed in the 1980s by crossing several breeds, including the Longhaired Whippet, they report, making the Whippet the probable source of the gene in the Windhound. Where did the Longhaired Whippet get the gene? There are two immediate possibilities. The Longhaired Whippet is an ancient variety that was restored in the 1950s by a single breeder who also raised Shetland Sheepdogs, which could have been the source. But it has also been suggested, the researchers say, that the gene could have come to the hounds by crosses between Collies owned by Queen Victoria and Borzois, another type of sight hound, given to her by Russian Czar Nicholas II.