Can you guess this dog's genotype?
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This is a Samoyed. The breed is white, biscuit, cream, or white and biscuit. This dog appears to be a solid white rather than cream, though it is difficult to tell since white coats are easily discolored. There are several things that can cause a dog to be solid white or to appear white.
White German shepherds are in fact a pale form of recessive red and will nearly always have a cream-tinted coat. This is most likely caused in combination with a modifier that dilutes the red in the coat to this pale cream color. This is a possibility.
Extreme white piebald can cause a solid white dog. It is unusual for the dog to completely lack color, however, and this also usually combined with a loss of some pigment in the eye rims, lips, and/or nose. Since this dog has fully pigmented skin, this is unlikely. However, piebalding is seen in the Samoyed breed.
A solid white dog can also be caused by homozygous merle, though again it is very rare for the dog to be solid white, pigment is nearly always lost, and the eyes are most often blue in whole or in part. This, however, is not possible because merle is not known to occur in Samoyeds.
So, what is this dog? In all likelihood, this dog is in fact ee recessive red with modifiers to turn in near-white.
However, there is also some evidence that shows that it could be caused by a combination of the recessive red gene (which removes all black pigment from the coat) and the recessive black gene (which removes all red pigment from the coat) working together. Though there is not a lot of evidence for it, it is an interesting hypothesis nonetheless. For the sake of argument, I am going to claim this to be the case. Thus:
This dog is possibly aa ee or fully unpigmented white (with pigmented skin).