Bleed through of color in offspring of two white GSDs?
I ordered an AKC research pedigree for the one 'mystery dog' in my Elly's 3 generation pedigree. Acc. to the AKC research pedigree, the mystery great granddam, registered as a sable, descended of two parents registered as white. Actually all dogs in the 5 gen research pedigree were registered as white.
Now I know that white is a recessive masking gene in the GSD and that two white GSDs will produce white puppies although they all carry color on a different locus.
Lisa suggested to me that there can be bleed through of color in whites, and Elly's 'sable' ancestor might have been registered incorrectly. A light bulb went on. What resurfaced in my mind then was the information given to me by a person familiar with the 'Rin Tin Tin' breeding program. Rin Tin Tin IV (the one in the 50s movies) showed a very light colored saddle, favored as it worked well for the black and white movies of the time. Lee Duncan himself is to have crossed whites in with the black/tans to get this dilute color. And the contemporary Rin Tin Tin kennel that line bred on Rin Tin Tin IV is said to do the same to maintain the color of Rin Tin Tin IV.
An incorrect registration can happen easily as 'sable' isn't a precise term in terms of genetics. A sable dog with tri-banded hair is an agouti in the language of genetics. I've heard the light colored saddles referred to as sable several times, too, and I can see how that happens. A light colored saddle can appear sable but doesn't have the tri-band hair of the agouti.
Does anyone know of bleed through 'sables' with known ancestry? The genetics of this may not be understood yet, but maybe more color genetics savvy members can comment on what is known about the genetics of this color?
I have to decide whether I will include this research pedigree in a genomic diversity analysis or whether I should dismiss it as incorrect, leaving a hole in Elly's otherwise multi-gen pedigree. Thank you for your input!
Rin Tin Tin IV: http://www.pedigreedatabase.com/germ...rin-tin-tin-iv
Chip v. Dog Pound (border terrier), CGC
Elly v. Rescue (GSD, GSRNE 346), HI(C), CGC, TT
RIP: Feli, Iris, Dago (GSDs), Bubi (spitz), Tanja and Robin (mutts)
Last edited by RunShepherdRun; 05-12-2015 at 06:23 PM.