From
http://whitedobes.doberinfo.com/
Are "white" Dobermans really albino?
"White" or "albino" Dobermans are not actually white animals. They are a pale tan or cream color, and only the areas which would normally be rust-colored are actually white. Also, these Dobermans have blue eyes -- not pink or red eyes. Because these dogs are not white and because they have blue eyes, some people claim that they are not actually albino.
pigmented fur -- The problem here arises because of a confusion about terminology. As discussed above in the "what is albinism" section, the terms "albinism" and "albino" encompass a wide range of pigment disorders. Many albinos -- known as "partial" albinos or "tyrosinase-positive" albinos -- do have some pigment. There are human albinos that may have yellow or brown hair, and some that can even tan in the sun. There are also non-human albinos with some pigment, in several different species. For instance, the "chinchilla", "beige", "himalayan", "burmese", "cremello", and "mink" mutations in mammals such as mice, gerbils, rabbits, horses, and cats are all thought to be due to mutations in the "C" series of genes (the tyrosinase-producing genes), and can therefore be considered types of albinism.
In fact, most types of albinos do have some pigment. Only "complete" or "tyrosinase-negative" albinos have a complete lack of any pigment. But notice that even the albinos with some residual pigment, the "tyrosinase-positive" albinos, can accurately be called "albino" -- and the mutations producing these albinos are still generally affecting either the tyrosinase, or "C", gene, or sometimes the "P" gene see the "what is albinism" section above. The terms "albinistic" or "albinoid" can also be used, but "albino" is indeed an accurate term even if residual pigment is present.
hair structure -- Hairs from several albino Dobermans were compared by a veterinary expert to hairs from normal black, red, and blue dobermans, as well as hairs from complete albino cats and white whippets. These comparisons, performed by Dr. David Prieur, determined that melanin pigment granules (melanosomes) are severely reduced in both number and in pigment content in the albino Dobermans, as compared to normal Dobermans. In addition, the melanosomes which do exist are significantly enlarged, shaped abnormally, and distributed unevenly. The albino Doberman hair shafts are distorted, and the diameter of the hairs is variable. In some ways these findings are similar to the hairs of blue and fawn dogs, whose hair also contains enlarged and abnormally distributed melanosomes. However, the albinos that were examined were NOT genetically dilute animals (they all carried B and D alleles, and were probably BBDD animals), and the albinos had a severe reduction in number and pigment content of the melanosomes, while melanosomes in blue and fawn dobermans are numerous and have normal pigment content. In contrast, the white whippet hairs (the result of an extreme spotting trait) had NO melanosomes, smooth hair shafts, and a constant hair diameter; and the complete albino cat hairs had large numbers of melanosomes which contained no pigment, also with smooth hair shafts of constant diameter.
blue eyes -- Even many complete albinos have blue eyes. For instance, the NOAH albinism site states "A common myth is that by definition people with albinism have red eyes. In fact there are different types of albinism, and the amount of pigment in the eyes varies. Although some individuals with albinism have reddish or violet eyes, most have blue eyes. Some have hazel or brown eyes." see the quote here.
Also, the International Albinism Center states "Iris color is usually blue/gray or light brown.... It is a common notion that people with albinism must have red eyes, but in fact the color of the iris varies from a dull gray to blue to brown. " see the quote here.
Eyes which appear blue can be produced without pigment because of the phenomenon of refraction. It's important to remember that the structure of the iris often has more effect on the apparent color of the eye than the absence of pigment itself. Think of the sky. Is there any blue pigment in the sky? No, of course not. So why does the sky look blue? It looks blue because the dust particles in the sky refract (scatter) light in a specific way, and light of different wavelengths is refracted differently. The structure of the iris in some species allows absorption, refraction, and filtering of the light that hits it, so that the eye may appear blue even when there is no pigment in the iris.
As stated by Dr. Mark Ladd, a veterinary geneticist: "The iris colour in an adult dog is determined by two layers. An inner layer, which gives rise to the blue eyes present in all puppies just after birth, is not pigmented; the blue colour arises because of an absorption of the longer wavelengths of white light before reflection back...The outer layer gives rise to the dark eye as it becomes pigmented from melanin production in the eye....Albinism means the complete absence of melanin pigment (Searle, 1981).If one accepts this view, then dogs such as the white Dobermanns, with blue eyes, can be termed albinos." In fact, blue-eyed albino mutations are known to occur in several different species. As stated by William Oetting (a widely-known expert in albinism from the University of Minnesota), "The blue eyes is consistent with albinism. Dogs have an iris which is blue if it contains no pigment (same as the Siamese cat, for example, which also has a type of albinism). Animals with little or no iris (mouse, rat) have pink eyes."
Additionally, as mentioned above albinos can even have BROWN eyes -- and the color of an albino's eyes can change over time. To repeat a quote already mentioned in a previous section, from the International Albinism Center: "An important distinguishing characteristic of OCA1 is the presence of marked hypopigmentation at birth. Most individuals affected with a type of OCA1 have white hair, milky white skin, and blue eyes at birth. The irides can be very light blue and translucent such that the whole iris appears pink or red in ambient or bright light. During the first and second decade of life, the irides usually become a darker blue and may remain translucent or become lightly pigmented with reduced translucency. " see the quote here. Interestingly, at least one albino doberman is known to have been born with blue eyes and has developed gold eyes along with darker fur pigment during his second year of life.
conclusions -- All current evidence supports the conclusion that "white" Dobermans are indeed suffering from some type of albinism. Like other "tyrosinase-positive" or "partial" albinos, they have a diffuse loss of pigmentation in the fur and may accumulate pigment with age. Like other albinos, they have unpigmented skin and eyes. Like other albinos, the trait is inherited as a simple recessive trait. Like several other types of albinism, they appear to have abnormal melanosomes. In fact, nationally recognized geneticists agree that these dogs are albino. Several experts in genetics, albinism, pathology, and ophthalmology have agreed that these dogs appear to be albinos, including G.A. Padgett, D.F. Patterson, M.F.C. Ladd, W.S. Oetting, J.P. Scott, and David Prieur. Interestingly, not a single expert in any of these fields has reached any other conclusion.
Dr. Oetting has stated "It sounds as if the dogs do indeed have albinism. ....These dogs sound like they have OCA1 resulting from mutations of the tyrosinase gene, a major gene in pigment formation."
G.A. Padgett, DVM, Professor of Pathology, has stated "I would agree with Dr. Patterson's suggestions (1982) that this is probably a mutation in the C series. I believe it is an albino, although not the classical pink-eyed tyrosine negative animal which we associate with this term. They are phototypic, and I believe there is little disagreement with this statement". Dr. Padgett also lists albino dobermans as partial albinos in his book Control of Canine Genetic Diseases.
David J. Prieur, DVM, PhD, of the WSU Dept. of Veterinary Microbiology and Pathology, has stated "Several years ago I expressed my concern regarding the breeding of 'white' Doberman Pinscher dogs. I expressed the opinion that the gene for the white coat was a deleterious gene and that the Doberman Pinscher breed would be better served by not incorporating this gene into the gene pool of the breed. Although these 'white' Dobermans have been shown not to be true albinos, they are tyrosinase-positive albinoids with a severe reduction of melanin in oculocutaneous structures.There have been numerous defects described in animals of other species with genes of this type.....I am unaware of any information, published or presented, since I originally expressed my concerns, which would lead me to believe that this gene is not deleterious."
Dr.M.F.C. Ladd, a British veterinary geneticist, has stated "Albinism means the complete absence of melanin pigment (Searle, 1981). If one accepts this view, then dogs such as the white Dobermanns, with blue eyes, can be termed albinos.....Unless much more evidence is forthcoming, I feel that the white Dobermann should be looked upon as an abnormality, known to exist and hoped to be avoided."
And J.P. Scott, PhD, a geneticist at Bowling Green State University, has stated: "Photophobia would constitute somewhat of a handicap to a working dog"; and "Something must be done. I realize that most breeders are responsible, selecting strains that seem good. But once an undesirable trait enters a breed, it is not an easy thing to eliminate".