Color
Two different color genes exist in the Dobermann, one for black (B) and one for color dilution (D). There are nine possible combinations of these allelles (BBDD, BBDd BbDD BbDd, BBdd, Bbdd, bbDD, bbDd, bbdd), which result in four different color phenotypes: black, red, blue, and fawn (Isabella). The traditional and most common color occurs when both the color and dilution genes have at least one dominant allele (i.e., BBDD, BBDd, BbDD or BbDd), and is commonly referred to as black or black and rust (also called black and tan). The red, red rust or brown coloration occurs when the black gene has two recessive alleles but the dilution gene has at least one dominant allele (i.e., bbDD, bbDd). "Blue" and "fawn" are controlled by the color dilution gene. The blue Dobermann has the color gene with at least one dominant allele and the dilution gene with both recessive alleles (i.e., BBdd or Bbdd). The fawn (Isabella) coloration is the least common, occurring only when both the color and dilution genes have two recessive alleles (i.e., bbdd). Thus, the blue color is a diluted black, and the fawn color is a diluted red.Expression of the color dilution gene is a disorder called Color Dilution Alopecia. Although not life threatening, these dogs can develop skin problems. Since 1994 the blue and fawn colors have been banned from breeding by the Dobermann Verein in Germany and under FCI regulations Blue and Fawn are considered disqualifying faults in the international showring.
In 1976, a "white" Doberman Pinscher bitch was whelped, and was subsequently bred to her son, who was also bred to his litter sisters. This tight inbreeding continued for some time to allow the breeders to "fix" the mutation. White dobermans are a cream color with pure white markings and icy blue eyes. Although the disorder is consistent with albinism, a proper characterization of the mutation is currently unknown. The animals are known to be tyrosinase-positive albinoids, lacking melanin in oculocutaneous structures, but no known mutation has been identified. Thus, these Doberman Pinschers are not actually white, rather they suffer from a deleterious genetic disorder that is associated with increased health risks.
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