Merle (coat colour in dogs)

English: 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. Some percentage of merle puppies could have eye defects and/or could be deaf. Genetically it is linked to the Silver dapple color of horses and the microphthalmia Locus of the Mouse.

Deutsch: Der Merle-Faktor ist ein Scheckungsgen, das zu Fehlbildungen der Augen wie dem Fehlen von Linse oder verkleinerten Augäpfeln bei Tieren führen kann. Die Mutation entspricht der Pferdefarbe Windfarben und dem Microphthalmia-Locus der Maus

Variation in expression

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  Extensive merle markings, with only small splotches of original black pigment.
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  Another light merle, with long coat
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  Extremely dark merle, close to being cryptic
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  Another extremely dark merle, with only faint lines for merle markings
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  Merle on saddled black-and-tan dog: yellow phaeomelanin remains unaffect while the black eumelanin shows distinct merle pattern.
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  Barely-there merle markings on a Beauceron
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  Distinct merle in long coat
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  Very large solid patch in blue merle dog; such patches are usually undesired in show dogs

Pattern combinations

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  Brindle and merle: brindle markings are uneven on body, merle nearly cryptic with only faint speckling on face, blue eyes, and broken nose colour
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  Clear brindle markings on the mask of a fawn dog
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  Cryptic merle on red coat
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  Merle on clear sable
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  Merle on heavily marked sable

Shade varieties

Blue Merle

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  Blue merle Catahoula Leopard Dog
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  Blue merle Great Dane with rusty discoloration, an undesired trait in many breeds where blue merle is an accepted coat colour

Blue Merle with tan

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  Homozygous merle
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Blue Merle And White

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  Blue merle Border Collie puppy
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  Blue merle Border Collie
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Blue Merle Tricolor

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  Threecolored Australian Shepherds, right with merle, left without merle
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  Blue merle Australian Shepherd
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  Blue merle Smooth Collie
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  Blue merle Rough Collie
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  Blue merle Shetland Sheepdog
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Red Merle

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  red and tan with merle (the tan color isn't changed by merle pattening)
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  A red-merle Smooth Dachshund
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  A female red-merle Australian Shepherd puppy

Red Merle And White

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  Red merle Catahoula Leopard Dogs
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  Red merle Catahoula Leopard Dog
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  Red merle and white Australian Shepherd
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  A 65 lb, 18 month Old, Red Merle Australian Shepherd (playing with a black Labrador mix).
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  Red merle and white Australian Shepherd
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  Red merle and white Australian Shepherd puppy
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Mixed groups

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  From right to left: merle, sable and tricolour coloured Rough Collies (Sable merle can look like normal Sable but not always! The coat can change in very different ways. That's the reason why Sable are "not allowed" to breed with any other merle gene dogs.)
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Homozygous merle

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  Blue homozygous merle: extensive white
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  Great Dane with homozygous merle and harlequin resulting in full white coat. Notice affected eyes.