Variations of Australian Shepherd colorsRecognized Aussie colors are solid black, solid red (liver), blue merle, and red/liver merle; each of these colors may also have copper (tan) points or white markings in various combinations on the face, chest, and legs. A black or red dog with copper and white trim is called 'tricolor' or 'tri', while a black or red dog with white trim but no copper is called 'bicolor' or 'bi'. This merle (M) is dominant, so heterozygous dogs (Mm) show the pigmentation pattern; however, when two merles are bred, the statistical risk is 25% of the offspring will end up with the two copies of the merle gene (homozygous). These dogs usually have a mostly white coat and blue irises, and are often deaf, blind, or both. In this case, the deafness and blindness are linked to having two copies of the merle gene, which disrupts pigmentation and produces these health defects.