All black and blue merle dogs have black noses, eye rims, and lips. All red and red merle dogs have liver or brown noses, eye rims, and lips. In general, however, black Aussies (self, bi-color, or tri-color) tend to have brown eyes, while red (self, bi-color, or tri-color) Aussies tend to have amber eyes, though these Aussies may also carry the blue-eyed gene. The merle phenotype in Australian Shepherds is very similar to the coat color in Mitf mouse mutants. In general, however, black Aussies (self, bi-color, or tri-color) tend to have brown eyes, while red (self, bi-color, or tri-color) Aussies tend to have amber eyes, though these Aussies may also carry the blue-eyed gene. The merle phenotype in Australian Shepherds is very similar to the coat color in Mitf mouse mutants.