Thursday, December 22, 2011

Mismark Case Study: Dalmatian

Dalmatians in their two accepted color varieties: black spotted and liver spotted. The central dog is liver, while the other two are black. Image is copyright free from Wikimedia Commons.
This Dalmatian? has a large patch and indistinct spots
Dalmatians have a very distinctive appearance, and their color standard has a quite narrow range of what is considered "acceptable." The spotted coat is caused by the combination of two genes: extreme white piebald and what is believed to be a modified form of the ticking gene. This is why the puppies are born white and the color appears later. This is also why patches will appear (where a puppy is born with some color), all caused by the extreme white piebald gene not removing all of the color from the body. Both acceptable colors are caused by the dominant black gene, thought the liver dogs are also expressing the recessive liver dilution. Due to the dominant nature of the black, there is a great amount of potential for mismarks. In fact, quite a remarkable number of mismarks are known in the breed, almost all of which are caused by recessive genes:

  • Lemon 
    • Moderately pale to very pale recessive red
      This Dalmatian is a lemon mismark
  • Orange
    • More red-ish recessive red
  • Blue
    • Diluted black
  • Fawn
    • I don't know if it's been documented
    • With blue possible, fawn (blue + liver) is possible
  • Tricolor
    • Tan spots in the same regions seen in tan pointed dogs
    • May be black or liver (potentially also blue or fawn)
  • Brindle
    •  Stripes on red, of course 
    • May be black or liver (potentially blue or fawn)
  • Trindle
    • Where stripes are seen in the points 
    • May be black or liver (potentially blue or fawn)
  • Sable
    • Has the potential for black, liver, blue, or fawn pigment
  • Indistinct spots
    • Spots with edges that aren't crisp
  • Improper eye-rim pigmentation
    • Pink either in part or in full
  • Too few spots
    • Very few or no spots 
  • Too many spots
    • When the spotting is too heaving 
  • Patches
    • Present from birth

This Dalmatian has too many spots
Since the cause of nearly all of these mismarks are recessive genes it is nearly impossible to remove the color from the gene pool. As such, they continue to appear. Some of the variations may even be considered rather common, while others are more unusual. However, it is quite remarkable how many variations are frowned upon, especially when it comes to such things as patches, the density of the spots, the distinctness of spots, and eye-rim pigmentation. By the nature of the two genes that go into making a dalmatian a dalmation (extreme white and ticking), all of these variations are not just very possible, but almost expected. Even all white dogs, since ticking/spotting is dominant, a dog without the spots is quite possible. Eliminating dogs who express these unacceptable variations from the population by not breeding from them is basically a pointless endeavor. The variations are common because some of what goes into the density and placement of the spotting is random chance. This is true of both the extreme white and the modified ticking. As such, eliminating the dogs from the breeding population will not prevent the undesirable phenotype from occurring. Removing these dogs only serves to decrease the genetic diversity in the breed.

This Dalmatian has incomplete eye pigment
The require for completely pigmented eye-rims is rather ridiculous, in my opinion, as extreme white piebald, by its nature, will cause a loss of pigment all over the body. As such, it is very common for the gene to cause a loss of pigment from the skin as well as the coat. In truth, part of what may cause so many Dalmatians to have black eye-rims is the presence of those spots. They grow from dark spots on the skin, and as such dogs with black spots around there eyes are more likely to have fully black eye-rims. However, chance may very well lead to a dog with virtually do face spots and completely pink eye-rims. It seems silly that the standard allows blue eyes but not pink eye-rims.

As I have mentioned time and time again in these case studies, frowning upon a dog just based on its color is absurd. Especially if the differences are minor, and even more so if the variation is a common one and occurs due to the nature of the genes that go into the making the breed's acceptable standard colors. Even worse, dropping these dogs needlessly narrows genetic diversity in breeds that already have serious inbreeding problems thanks to closed registries and heavy selective breeding.


  1. It doesn't surprise me that a lot of the stuff on color in the Dal breed standard is based on genetic ignorance of color inheritance.

    Originally, Tricolor Dals were highly favored, until some people decided they were a result of 'mixing' between Liver and Black Dals and had them written out of the standard (apparently crossing Liver- and Black-spotted dogs was frowned on back then). A prime example of blood-purity fixation based on ignorance of genetic facts.

  2. Here are some excerpts on Tricolor Dals from the late 1800s, showing how it took less than 20 years for attitudes to change about them:





  3. That second dog doesn't look like a purebred dal at all, regardless of color. Not the best example imho.

  4. Wow, Pai, I had no clue! Yeah, that's rather misguided. It amazes me that people didn't make connections to the same colors seen in other breeds. The genes are, for the most part, universal, and if you pay attention it's really obvious that the tricolor is based off of the black and tan of other breeds. I also doubt breeding data supported that assumption, since there should be no correlation between mating liver to black and producing dogs with tan spots. It makes me wonder if modern breeders would deny that the color was ever accepted, let alone preferred.

    Anon, I very much see your point. However, she does look more Dal to me than, say, pointer. The spots are rather large and clearly defined for a ticked breed. She could be a really oddly marked, off-type Dal. It does happen. Or she could be a mix, possibly very heavy on the Dal. I have seen Dalmatians with similar markings and structure. I personally thought she just looked old and fat, but I don't have a great amount of experience with the breed.

  5. this is Astro.. a dal who is sooooo white.. has two blue eyes.. and only his upper lids are black.. the lowers are pink

  6. Astro is quite an interesting looking Dal! I have seen a couple with that much white before. They're the exception and show, in some way, how the ticking/spotting genes work. Dalmations are really white under all of those spots and the spotting/ticking gene sort of causes color to break through the white. That's why the breed is born white except for the odd patch. :)