Monday, February 15, 2010

"Sable"..Ultimate Natural Beauty!

Ah, sable! The very word evokes images of ladies' mink stoles of yore; plush and rich in color. It's not often these days that we see an actual Real McCoy fur coat; so when it comes to dog coat color we sometimes need to refresh our collective memories a bit in regard to natural coat color and the genetics involved.

The AKC glossary defines "Sable" thus:

Sable: Coat color produced by black-tipped hairs on a background of silver, gold, gray, fawn, or brown.
But a genetic sable may display an appearance very that is very different from this restrictive, limited definition.
First, let's back up a bit to the biology of coat color. There are two basic coat pigments. There is "eumelanin" which is your basic black, and the other is phaeomelanin which produces red/yellow. (The prefix "eu" means "true", while "phaeo" is from Greek meaning "color of the twilight sky".) All other coat colors are variation on these two foundation pigments.

Coat color genes work by reorganizing the basic pigments. Agouti genes result in a banding of individual hairs; a combination of eumelanin and phaeomelanin on each individual hair. Other genes may dilute black eumelanin to blue or brown....or two recessive dilute factors can combine to form the color of the Weimeraner. Still other genes modify phaeomelanin to form shades of red, orange, yellow, or cream.

Various pattern genes rearrange the color..for instance, the gene for the tan point pattern instructs the phaeomelanin to congregate in "points" above the eyes, on the face, legs, under the tail and on the forechest. Brindle genes instruct the eumelanin to form in stripes. White spotting genes remove color pigments completely, leaving defined areas of white. Merle dilutes whatever underlying coat color is present. The result can be a splotchy effect on phaeomelanin, or a silvering of eumelanin to result in "blue merle".

In genetic parlance, sable has traditionally meant phaeomelanin added to or replacing the black coat color. Agouti is the technical term for haircoat banded with different shades of eumelanin and phaeomelanin. It's often referred to as a "wild" type coat. And it's tough to beat Mother Nature when it comes to beauty! Think of that sable or mink coat, if you are lucky enough to have actually seen one!.

We normally think of black tipped hair when we think of a "sable" dog. But, not all dogs that are genetic sables have extensive black tipping. Some sables lighten with age or have banding that does not fit the "tipping" description....the hair can be banded in unusual ways, perhaps darker at the base and lighter at the tips. Some breeds like Collies have sables that do not have much black tipping if any! Some pups are born dark sable and lighten with age. Many dogs registered as "orange" or "red" are actually genetic sables.
Of course there are many examples of traditional sables....German shepherds often have a heavy sable coat with the heaviest black tipped hairs in the "saddle" area.
Fred Lanting wrote an interesting article about sables, where he notes there exists:
"So-called "golden sable" resulting from good brown lower parts of the guard hairs but not as much black tipping as some other dogs pictured in this article."

I believe we should not hold strictly to the AKC definition of "sable" as dark tipping, because many of our genetic sables do not have much dark tipping. "Sable" as a color category that would include anything from wolf sable to cream sable to orange sable, to dogs that appear yellow, red or orange!

Sable....true natural beauty!

Thomas Jefferson wearing a sable coat

Sable Marten (Weasel family)

1 comment:

  1. some breeds, like the Collie, the gold color is actually referred to as "sable" in their breed standard. Hey, st least ONE breed managed to label it correctly!