Merle is a colour combination in
dogs’
coats. It is a solid base color (usually red/brown or black) with lighter
blue/gray or reddish patches, which gives a mottled or uneven speckled effect.
Although most breeds that can have merle coats also typically have white
markings (such as around the neck, under the belly, and so on), and often tan
points (typically between the white and the darker parts of the coat), these are
separate colors from the merle; some dogs do appear completely merled with no
white or tan markings.
Merle is actually a
heterozygote of an
incomplete dominance gene. If two such
dogs are mated, on the average one quarter of the puppies will have eye defects
and are often deaf. Knowledgeable breeders who want to produce merle puppies
mate a merle with a nonmerle dog; roughly half the puppies will be merles
without the risk of vision or hearing defects.