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This is Jamie and he is an American cocker spaniel. So, what's his genotype? Well, it's pretty straightforward.
Clearly, Jamie is a black and tan. However, one of the major questions presented with him is whether he carries recessive black or not. Both dominant and recessive black are known to occur in cockers, though recessive black is more unusual, and as such it's difficult to be sure. There are many who believe that the muddying of the tan points, such as is seen in Jamie, results from the presence of the recessive black gene. However, I don't believe that this is the case. To begin with, I found little evidence for it other then a lot of "some think this is true." No information on breeding data, no genetic research, etc. It is quite difficult to say, though, as the recessive black gene is so unusual in the dog world. It is possible that they simply haven't gene-tested dogs who are recessive black. Or, it may just be that the smutty tan in completely unrelated. As I said, I don't think it is caused by the recessive black. Again, I look at other dogs. Tar heel, penciling, and other phenotypes that muddy tan points are known in many breeds that never have recessive black, such as the Manchester terrier and Rottweiler. It is quite unusual for a certain phenotype to be completely exclusive to one particular breed, and as such looking at the dog as a whole can be rather telling. Despite this, it does not eliminate the possibility that Jamie carries recessive black. However, for the sake of argument I am going to say Jamie is atat tan pointed.
As for the intensity of the red seen on this dog, it is rather intense, but not as intense as it could potentially be. I suspect that Jamie is Cch moderately intense red.
In addition to this, the black seen on Jamie's muzzle clearly says "mask" to me. Masks are seen in the breed, but buff (recessive red) is so common that I doubt he is homozygous. As such, I suspect that he is Eme masked carrying recessive red.
So, that would be atat Cch Eme or masked black and tan with moderately intense red.