Adopts | MYOs | Breeding | Genetics
The "E" locus is in charge of what parts of a dog can produce eumelanin (black) and phaeomelanin (red), buts its easier to just think of it as the masking gene.
Technically, Em is the top-dominant, so a dog with Em in its genes will always have masking. Masks are areas of black pigment on the face, chest, and sometimes paws in extreme cases. The mask is the same shade as the rest of the black pigment, and covers over everything but white spotting. Masking can be minimal and stay just around the muzzle, or extend down the chest and paws. In real life, it's a bit debated on what causes extreme masking. When I do dog species, I usually do extreme masking if a dog has two copies of "Em".
Next is "E", sometimes called "Extension" as it allows the patterns determined by the "A" and "K" loci to show as intended.
Last is "e", reccesive red. Two copies of "e" prevent eumelanin (black) from appearing in the coat at all. You can still tell what eumelanin base a dog has by looking at its nose color.
the three examples above are shown with all three possible outcomes of the "E" locus:
1) a black and tan saddle. shows the typical masking confined to the face only.
2) a lilac and offwhite point shows how masking cover up points, and how it stays the same shade as the rest of the eumelanin.
3) a red and blue sable. shows and example of extreme masking.
