Originally Posted by Jaymicsi
Thank you KMDogs for the help. I was really just interested in knowing what an all Chocolate would do to a blue as far as pups. I understand you would need more info about there parents. I was looking for a basic idea. I called it irish spotting because that is what I have read in numerous genetic articles concerning color variations. My blue pit is Dark blue and has white feet, chest, and on her face. The chocolate is a dark chocolate with no white anywhere. The chocolate pups parents are both chocolate carries, the mom is a red, red nose and the father is a champagne red nose. That's all I know. Thanks for the input. I was slightly confused with what I've been reading and was curious about whether or not the dilute gene (choc) to dilute gene (blue) would cause the chocolate to dilute further.
I personally think the choc/brown would dominate in that litter but who knows...anyway
B (brown) locus-Chocolate is bc
The alleles at the B locus are related to the production of tyrosinase related protein 1 (TYRP1) and determine the degree to which an animal expresses tyrosinase, an enzyme related to the production of melanin, in its coat and skin (including the nose and paw pads). There are two known alleles that can occur at the B locus:
B = Black
b = Brown (includes several alleles - bs, bd and bc)
B is dominant to b. An animal that has at least one copy of the B allele will have a black nose, paw pads and eye rims while an animal that is homozygous for any of the b alleles will have a liver nose, paw pads and eye rims.
D (dilute) locus
The alleles at the D locus (the melanophilin gene or MLPH) are related to the dilution of eumelanin and/or phaeomelanin and determine the intensity of pigmentation. There are two known alleles:
D = Not Diluted
d = Diluted (Black becomes grey or blue; brown becomes light tan or "Isabella")
D is dominant to d. Homozygosity of d is sometimes accompanied by hair loss and recurrent skin inflammation, a condition referred to as either color dilution alopecia (CDA) or black hair follicular dysplasia (BHFD) depending upon the breed of dog.
As for IRISH SPOTTING, it is an actual genetic term. I personally don't hear it a lot but I see a lot of dogs with it. My girl Cookie has it.
S (spotting) locus
The alleles at the S locus (the microphthalmia-associated transcription factor gene or MITF) determine the degree and distribution of spotting of an animal's coat. There is disagreement as to the number of alleles that occur at the S locus, with researchers postulating either two or four alleles. The four alleles postulated are:
S = Solid colour (small areas of white may appear on chest, toes or tail tip)
si = Irish-spotting (white on muzzle, forehead, feet, legs, chest and tail)
sp = Pie-bald spotting (large areas of white)
sw = Extreme pie-bald spotting (Extremely large areas of white, almost completely white)
S is dominant to s. DNA studies have not yet confirmed the existence of all four alleles, with some research suggesting the existence of at least two alleles (S and sp) and other research suggesting the possible existence of a third allele (si). It has been suggested that what appears to be the result of an sw allele is in fact the result of plus and minus modifiers acting on one of the other alleles. It is thought that the spotting that occurs in Dalmatians is the result of the interaction of three loci (the S locus, the T locus and F locus) giving them a unique spotting pattern not found in any other breed.