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Main > Brindle German Shepherd Dog (88 replies)

by vonissk on 16 October 2012 - 01:10

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 http://homepage.usask.ca/~schmutz/brindle.html


But if you read through the other link and the one I just posted never is a GSD mentioned. In some breeds black is dominant. It is not in the GSD, it is a recessive. The only way you can get a black puppy out of 2 colored--other than black--parents is if both of them carry the black recessive. Simple genetics.................

by Elkoorr on 16 October 2012 - 01:10

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For interested folks, here is the pedigree of the above mentioned pup http://www.pedigreedatabase.com/dog.html?id=708869 . She is still with me. There are no obvious signs of brindle markings. She is of sable color (cream-black tipped) and might carry bi-color, like her sire.

by vonissk on 16 October 2012 - 02:10

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Joined: Fri Dec 30, 2005 05:20 am

She is a beautiful girl. No I see no signs of brindle markings.

My Sister dog, who is a wolf gray sable, will be 5 in Feb. That spring when she was such a baby, I noticed dark streaks in the tawney color that some (most) sable pups are. I posted it on here and several people commented on the brindle like marfkings and maybe it wasn't a lost color after all. But a little later when she started getting her true colors in, those markings disappeared................I didn't think it was genetically possible but I did think the markings were strange...................

by Elkoorr on 16 October 2012 - 02:10

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Joined: Thu Sep 27, 2007 02:18 am
Yeah, vonissk, maybe its attached to a locus somewhere in the sables. The markings were defenitely there and not just a fluke of light reflecting between ribs. Who knows :)

by GSD Lineage on 16 October 2012 - 02:10

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Recent genetics have changed the way we understand color.
All Sables Bicolor solids and saddles are "Black" dogs. 
the agouti series decides the pattern.

Solid, saddle, Bi color and Sable are actually patterns. :-)

White GSDs are actually pale reds. For this reason the white shepherd will become it's own seperate population unless they desire to look more cream or red like Golden retriebers or Setters.

by BlackthornGSD on 16 October 2012 - 03:10

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OK. I'll explain. Brindle and dominant black are ruled by the K locus. On that locus, Kb is the notation for solid black, which is dominant to Kbr (the notation for brindle). In order for the agouti locus to factor into the appearance of the dog, the K locus is Ky --the notation that indicates that the phaelomelanin expresses itself. All GSDs are thought to be Ky on the K allele because otherwise, the agouti locus wouldn't come into play.

http://homepage.usask.ca/~schmutz/brindle.html#kk

However, one thing that I don't see addressed is how we would see a black and tan dog with brindle on the tan points. There *must* be something else going on there. In horses, brindle colorate is caused by "chimeras" -- horses that carry 2 sets of DNA--so perhaps all brindle GSDs are really chimeras?. It's also possible that some sort of mutation(s) on some modifier genes is responsible for the brindle legs on a black/tan dog. It's also possible--even likely, according to the article linked--that there's some additional genes/loci at play, too,so that the explanation doesn't neatly fit into our simpified locus/allele "shorthand" understanding.

So, either there is no brindle in GSDs... or there's some mutation that occasionally causes/allows brindle "striping" on the tan portions. The page on brindle actually gives an example of a black/tan dog with tan points brindled, but it doesn't explain how it's possible. It sounds like there must be some modifiers or mutations (which again makes some sense according to the research article linked) that occasionally allow the tanpoint pattern to show up on a brindle dog.

In rare cases the brindle stripes are confined to the areas that would typically be tan in a black-and-tan dog. This Staffordshire Bull Terrier, Taisto, is such a dog. Taisto was mated to a fawn/red female who was ay/ay and therefore they had some pups that were "full body" brindle not just brindle on the tan points, at being recessive to ay.

To get back to the initial premise proposed--does recessive black "hide" brindle? The answer is no. A black dog with the gene for brindle is generally a "black brindle" where all of the black areas are brindled. A dominant black dog can be KbKb or KbKbr -- so it could appear black but produce brindles.

And the other problem with the idea of brindle "hiding" under recessive black is that the agouti allele heirarchy in GSDs is sable/tanpoint/black. So, why would recessive black hide the brindle color but sable and tanpoint wouldn't? How would that work? Are you proposing that there is a brindle pattern on the agouti allele?

Christine

by GSD Lineage on 16 October 2012 - 04:10

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Joined: Tue Sep 18, 2012 07:05 am
I honestly have to read that article carefully. I don't know much about brindle as it is not a color in the GSD at the moment, I'm planning on reading up tonight as a treat because I enjoy the color stuff. What I can't understand is why people are calling black dominant or ressevive. All black is dominant to red/buff/cream/silver. agouti and maybe also other loci like k affect if black is reduced or localized to areas by some sort of pattern. Fun Stuff....
I have seen the brindle with black saddle on the dutch shepherd.

Also, Many of the Fawns in the Boxer are actually light sable dogs (Black base coat) ... the black mask is the give away. You never see a black mask on a yellow lab, Irish setter, buff cocker white shepherd those are true reds. Chocolate labs and reb dobes are diluted blacks not true reds (Liver).

Have you all seen the new pedigree picture feature on the first page of pedigree database?
That is fun, it lets you see how the patterns and colors are passed down in a variery of breeds.

by BlackthornGSD on 16 October 2012 - 05:10

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Joined: Wed Jul 25, 2007 08:57 pm
GSDs are unusual in that they are one of the few breeds that gets its solid black coloring through the agouti allele. Most solid black dogs are going to be Kb on the K locus ("dominant black"). A solid black GSD would be KyKy and would have the overal black pattern controlled by the agouti allele (recessive black because the pattern is recessive to wolf-sable and tanpoint).

Christine

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