Elsewhere on this site, we shared a rather vivid description about the origin of the term used to describe the dog color: “Isabella.” This same color, a dilute, is commonly referred to as “pearl” in Rat Terriers. And here’s where we call on our genetic buffs to bail us out if we get into trouble.

“Pearl” is the dilution gene that causes a black dog to become blue and also causes a liver dog to become “pearl.” In Ratties, the pearl is evidence that the double recessive of “dd” is present, the Eumelanin color diluted. Dilution and liver are both recessive and pretty rare, so “pearl” isn’t a common color. We’re always a little leery of “quicky clues,” but we’ve read that very often, the easiest way to determine whether a sable dog is a dilute or non-dilute is to look at the nose leather. Black or Chocolate nose leather = Non-dilute. Blue or Pearl nose leather = Dilute.

“Rat Terrier Reading” by lulunjay
Find and support this artist’s work here