German Shepherds Forum banner

1 - 20 of 51 Posts

·
Registered
Joined
·
1,492 Posts
The chart is wonderful, thanks a lot. Do I understand that there is one locus for coat color with four alleles: a, as, at, and aw with aw dominant(partially?) to everything else, as dominant to at and a, and at dominant to a? I guess I should look at your explanation. Anyway it's great. Mary Jane
 

·
Registered
Joined
·
169 Posts
Discussion Starter #3
You've probably explained it better than I have /ubbthreads/images/graemlins/01_smile.gif There is, however some debate that the bicolor ("at" allele) is not actually determined in the agouti locus. But for all intents and purposes, this melanistic feature is included "supposedly" without affecting the reliability of the chart.
 

·
Registered
Joined
·
386 Posts
Hmmmmmmmm

Well ok I suck at reading thisLOL. I have a (black)Sable, both sire and dam are Sable. On sire side grandsire is a (black) Sable and Granddam is a Bicolor. On dam side the grandsire is black/tan and granddam is a Sable. With this info can one determine what type(aw+aw, ect) of Sable my dog is?
If one wanted to breed for a specific color how do you determine what color to breed to what? DISCLAIMER: I am not a breeder and have no intentions of breeding.
Thanks
 

·
Registered
Joined
·
3,755 Posts
Re: Hmmmmmmmm

Your puppy is either Sable carrying Sable, Sable carrying black, or Sable carrying black and tan.....it is not that easy to figure out due to the presence of the Bi color bitch...they usually carry black so you do not know what the sire inherited from his dam, black or black and tan....do you know what the other colors were that appeared in your pups litter?

Why do you say your puppy is a black sable? Do you have photos of him you can share? Especially of his legs feet and stomach area? lol
 

·
Registered
Joined
·
3,755 Posts
Re: Hmmmmmmmm

OK, I went and looked at your photobucket bucket page lol I would agree he is a black sable...with my hypothisis I feel he is a sable carrying black. I say this because I feel that black sables are actually sables carrying black that also inherited the bi-color patterning.....my guess is that if he were bred to a black bitch you would get nothing but sables and blacks.

JMO
Cherri
 

·
Registered
Joined
·
3,755 Posts
Re: Hmmmmmmmm

Ok me again lol I went and looked at your boy's pedigree and it notes colors....it looks like his sire was a Black and tan from a sable sire and a black and tan dam that had a black sire (so we know the gene was there as the your dog's sire was black and tan and had to carry black...now the dam was sable with a black dam so we know for certian that the dam carried black...so the available color genes to your boy were sable, black and black and tan...but two possible chances of the black gene...based on his coloring I would say he is sable carrying black (sorry if this post is all out of wack I was interupted by a phone nutrition consult and now I forget where I was going with this lol)
 

·
Registered
Joined
·
28 Posts
Does anyone know how while shepherds came about? I know that there is a lot of inbreeding in them, but do they devolp during breeding of other colors or is it a mutated gene in them?
 

·
Administrator & Alpha Bitch of the Wild Bunch
Joined
·
13,571 Posts
Do you mean White GSDs?

White is a simple recessive masking gene. A White GSD carries genes for normal coat colors, but a separate gene on a separate locus can mask the normal coat color and make the entire dog white.

It is NOT true that thre is "a lot of inbreeding" in them, nor is it a mutation.

White bred to white will always produce only white pups, as both parents will contribute the white recessive gene to the puppies. White puppies can show up in litters from colored dogs, if both parents carry the recessive white masking gene and two recessives (one from each parent) combine in a particular pup.
 

·
Registered
Joined
·
1,708 Posts
An old thread but a new question...

Is the info below accurate?

http://www.4germanshepherds.com/white_german_shepherds.htm

Quote:Good" breeders won't let a white breed into their lines. It is not only a Disqualifying fault, the white gene also DILUTES the colors of the following generations of dogs coming from that line. Breeding a white to a black/tan (or other accepted color) washes out the colors of the offspring. If allowed to continue, in a few generations 'normal' colors would be whipped out.

For this reason, the gene pool available to the white German Shepherd is very narrow. Because of this, they are more prone to genetic disorders. They also can get skin cancer, which normal color shepherds do not get.

The black dog will IMPROVE the pigment on any standard color dog it is bred to, so they are often used to breed with 'more usual' color German Shepherds.
As a masking gene (& recessive), wouldn't the expression of white be an all or nothing phenomenon (barring the light cream shadings which are sometimes present). IF black is a true recessive, wouldn't it fail to express unless the dog is homozygous for it? Or are they more accurately co-expressed? Given that white dogs have normal dark pigment are they more prone to skin cancers? Are they really more prone to other genetic disorders?

IF the masking & black genes are co-expressed, wouldn't that too be largely an all or nothing phenomenon, ie those dogs heterozygous for each gene would have a fairly predictable color, not color that faded or enriched with subsequent generations? Regardless of the passing of generations, if co-expression is seen, wouldn't it be the same heterozygous state that's inherited/expressed? Wouldn't color fading or enriching generally be expected with additive genes?

Although I think the breeder's info could be wrong, this isn't intended as a criticism of her. She doesn't breed whites & might not be aware of the details associated with its inheritance. I don't breed whites, or any other color, so I could be completely wrong in how I've interpreted the little I've read.
 

·
Registered
Joined
·
355 Posts
No - it's incorrect. it's not the Extension Locus that dilutes the tan color - it's the Intensity Locus - now if my theory on the Intensity Locus and cream in the coat is right - breeders are selecting for more white in the coat - so by default they are selecting for more dilution if bred to a colored dog.

For the health - hogwash - I imagine that they wouldnt have become recognized overseas if the gene pool was so small. additionally - we're very snarky about our genetics. Most of us are members of the WSGenetics Project - which is our way of looking at diseases - the very same diseases that affect German Shepherds. You can have a look at that here : http://www.wsgenetics.org It may seem like alot - but I imagine that's because we're very good about collecting and displaying the information on our breed. I know Majorie is working on one for the GSD - which is great too


And the thing about breeding to black is an old wives tale that alot of people subscribe to. It's possible that maybe carrying the recessive allele for black will make the black blacker, but it wont change the red in the coat - that would show some incomplete dominance - but I've never seen anything to that affect. As far as I know the solid black coat is simply the expression of no patterm at the agouti locus.

As a masking gene the white only affects the fur - not the skin. I've posted pictures of my own dogs for you where you can see there pigment (leather) is very dark - Ruby came out with better pigment than a couple of colored litters I've seen. Additionally - it is all or nothing - you're either homozugous or not - if you're not the dog might carry for it.

The black also - though like I said there is some possibility that there might be some incomplete dominance...though as I said - I've never seen any research to that.

White Shepherds are not any more prone to cancer because their skin isnt any different than that of a colored dog. The white doesnt make them anymore prone to *anything* that a colored German Shepherd is not just as prone to.

The information is incorrect - and displays the same bias that is the reason I am perfectly happy seperating from the GSD as they have done in Europe. It's an old wives tale with no basis or research behind it to support it.

Additionally - if you are interested in the mode of inheritance of the white coat in the GSD - the link I provided before to Sheila Schmutz - she has published something in the Journal of Heredity in that regard.

One last note - the cause of white in Shepherds is exactly what causes yellow in labs - that's just the extreme level of cream there.

~Cate
 

·
Registered
Joined
·
10,225 Posts
I think there is a little merit to breeding white dogs potentially diluting the lines, not because the dog is white but because we have no idea what the color of the dog is UNDER the white. If you're breeding a deeply pigmented and richly colored dog that is white from the masking gene and consistently do this, then no, there will be no paling of color. However, if the dogs are weakly colored underneath the masking gene, well there you go. It's not directly the white, only indirectly and only because we don't see what's really going on. Also, I think the author may be influenced by what is seen in most litters that breed a colored to a white dog- black and silvers, mostly tan with little black, just a bunch of pet breedings. I wonder if the author looked into the good BBS breedings. Just my two cents, I could be wrong, though.

Everything else said sounds off base to me. Also, what about the whites with poor pigment? There are whites with pale noses and skin, do those have health issues?
 

·
Registered
Joined
·
355 Posts
DianaM - I do agree on that side - I really think that the intensity locus or something like it is what causes the cream - and as many breeders select against the cream coats, more dogs are going to have the dominant dilution at the I Locus.

Not that I have seen - snow nose is something that affects alot of the extension locus dogs - including the lab - and I havent seen any negative associations with it - I just dont like it o_O

As far as not fully black leather - as far as I can tell it's generally uncommon. I believe Albinism is not something the GSD breed carries for that I know of - just as they dont carry for blue eyes. The dogs will have pigmented skin - unlike other non-extension white dogs, which I *believe* would mean no more health issues than the deeply pigmented white or colored shepherd.

~Cate
 

·
Registered
Joined
·
169 Posts
Discussion Starter #17
About the health: Sometimes traits that appear to be unrelated (i.e., color and behavior) are in fact linked. Overselection for a single trait can possibly result in some unknown detrimental trait that is closely positioned to seemingly irrelevant loci in a section of dna.

Some old wives tales may have some substance to their claims, meaning "often associated" from generations of practice, and perhaps limited to the experience of particular bloodlines. But due to the complex interactions between many different genes, perhaps not always found true, or perhaps not affecting the entire litter. I believe in Australian Shepherds, breeding merle to merle color is lethal to 25% of the offspring?

I doubt there is any conclusive evidence against the health in white shepherds (or it would not even be disputed), but since they are not technically my chosen breed, I've not devoted much interest in them. As many emails as I get about them though, I'm going to start refering them to Cate ;-)
 

·
Registered
Joined
·
355 Posts
lol - bah - what can I say - I learn out of self preservation. As I said - we keep a very tight hold on what we do in terms of genetics through our genetics project. Now keep in mind - not all white breeders subscribe - but most of the WS breeders do here in the states. In Europe - at least with the swiss - they are anal retentive about testing (which is good). In order to be considered for breeding all the animals have to be health tested at the universities in Bern or Zurich.

As for conclusive evidence - D.P. Sponenburg mentions in the Genetics of the Dog that there have been studies looking for health issues related to the coat, and none have been found :p

The other good refrences are Sheila Schmutz and the http://www.wsgenetics.org for people trying to find out more about whites. The genetics project has a very large database for everything that has been submitted, both bad and good and a brochure for affected-by statistics.

~Cate
 
1 - 20 of 51 Posts
Top