Sunday, May 27, 2012

Guess the Genotype #73

Can you guess this mamma dog's genotype? What about her breed? What about the father of this litter?

Image from Wikimedia Commons under a Creative Commons license



Through some quick Google searching, I was actually able to track down the Finnish kennel that produced this litter of English pointers. The mother is known as Elli. Through this, I found individual pictures of each puppy (one, two, three, four, five, six, seven, eight), along with information on the father, Tasu, who can be viewed here. There's even more pictures of the litter and father here. There was even a repeat breeding done, and through this you can see a bit more variety. Despite the fact that I was able to find all of this information, I did my guesses on genotype before doing the searches.

So, what's the mother's genotype? Well, clearly Elli is a solid black, but you can tell a lot about what she carries by looking at the puppies. First, there are  several puppies that can be seen in the image above that indicate that she most definitely carries liver, which would make her Bb black carrying liver.

She also carries some form of red, since there is clearly a red puppy. However, is that puppy recessive red or sable? Considering the fact that the puppy appears to have no black hairs on its body at all, I suspect that it's recessive red. For this to be the case, the mother has to be Ee normal pigment carrying recessive red. This is confirmed when looking at the red puppy at a younger age. Dogs that are clear sable will have a black overlay at birth that fades with age. This pup didn't have that.

Also, for the mother to be black in the first place she must be expressing one of the two forms of black: dominant or recessive. The breed appears to have the dominant form of black and it appears to be near-fixed, with only the occasional dog expressing one of the Agouti variants popping up (mostly tan point, it seems, the inheritance of which one breeder states is "not well understood" ha!). Anyway, due to the near-fixed nature of the gene, Elli is most likely KK dominant black.

Last, but not least, if you look closely at the image you can see the white belly of a puppy peeking through between two of its brown siblings. Despite the fact that the mother has apparently little to no white herself, she must carry one of the alleles on the Spotting locus. It's hard to tell based on just a puppy belly, but pointers come in both piebald and extreme white. I suspect that Elli is Ssp solid carrying piebald.

So, that would be Bb Ee KK Ssp or black (carrying liver, recessive red, and piebald).

My suspicions were that the father was the same genotype, except liver due to the number of liver pups present in the litter picture, making him bb Ee KK Ssp. Of course, after doing my research I found that the father is, in fact, not quite what I thought he would be.

To begin, he is clearly extreme white piebald black. He also has prominent ticking, which is a trait I didn't even think to take into account. However, the Ee KK part of my guess appears to be true. As for the rest of the genotype, he appears to be Bb spsw Tt. The reasons I suspect he is not homozygous for extreme white (sw) is due to the fact that in one of the two litters he had with Elli, they threw a piebald puppy. There can be a lot of variation seen in both the piebald and extreme white genes, including whether or not a carrier shows any indication that they are a carrier. Though I could be wrong, I believe that Tasu is spsw but with modifiers that either make him a very minimal piebald or allow the extreme white gene to cause him to have less color. As for ticking, I believe him to be Tt due to the comparatively small number of pups that appear to have ticking as he does.

I suspect that my original assumptions about the Spotting allele Elli carried are wrong due to the sheer number of puppies in the two litters that are extreme white (of the six, only one is clearly piebald). So, instead of Ssp I believe she is Ssw solid carrying extreme white. In addition, due to the number of ticked puppies versus those with clear white (only one or two puppies are clearly ticked), I suspect that Elli is tt no ticking.

So, that would make Elli Bb Ee KK Ssw tt or black (carrying liver, recessive red, and extreme white) and Tasu Bb Ee KK spsw Tt or white and black ticked (carrying liver, recessive red, piebald/extreme white, and non-ticked).

7 comments:

  1. Interesting, I would have never guessed pointer and definitely wouldn't have thought that amount of variety was possible from the two parent dogs.

    I wonder what the benefit of a black pointer is? They can't be easy to see in the field, right? And why this breeder chooses to take that gamble using her to breed.

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    1. It can be quite surprising what can come out of parents sometimes. A favorite example I like to give is Ebon's litter. The father was yellow and the mother chocolate, but every last puppy was black. Genetics can throw some surprises sometimes!

      That is a good question, and I don't know if there would be any downsides to working with a dark dog. Looking at some other breeds, the German pointers (shorthaird, wirehaired, and longhaired) frequently come in near-solid or even solid liver, which would blend in really rather well in the field. However, it doesn't appear those that hunt with them have any problems. If nothing else, you can always throw a hi-vis collar on the dog.

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  2. hi from finland and from claypond's kennel :-)
    absolutely wonderful study!!
    this breeder can tell you that she has a mission .... keep the solid pointers alive. solids have been part of english pointers from the begining and i noticed that they became more and more rare - so i decided to use a solid parent in every litter i breed.
    so i can give my tiny share for this absolutely beautiful breed and all the colours and variations.

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    1. Variety is better than conformity, in my opinion, so it's good to see a breeder that's not trying to make every dog look exactly the same.

      One good advantage to solids is that they have a lower chance of having pigment loss in their cochleas, which causes a form of deafness that can sometimes pop up in dogs with a lot of white.

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  3. i forgot ... if you want to see more photos of all colours from claypond's look at my gallery:
    http://claypondskennel.kuvat.fi/kuvat/POINTTERI+-+CLAYPONDS+KENNEL+-+ENGLISH+POINTER/
    tiina

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  4. We have one of these puppies and his progeny have only been black and orange up to now.

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