White pants? Ooops, I mean white jeans. Eh, make that albino genes. As far as I know, no one has worked out the genetics of albinism in ferrets (except in a basic manner), but I would expect it to follow the basic rules and conditions of albinism in other mammals, BTW, all vertebrate groups can and do exhibit albinism from time to time. It is a common mutation. Essentially albinism is caused by a mutation that prevents the formation of pigmentation. The external appearance (phenotype) can be the result of several different mutations within the chromosomes (geneotype). Albinism can be caused by a mutation that prevents the body from manufacturing the pigments, a mutation that prevents the body from recognizing the proteins that key for the pigments, or even the body's inability to make the proteins that tell the body to make pigments. Three different reasons (from a possibly infinite number), but all look the same. However, in most cases of mammalian albinism, the reason is a mutated gene that prevents the manufacture of pigments. In the vast majority of cases, albinism is a recessive trait; that is, it cannot express itself without having two copies present. Albino does not "blend," that is, having a single gene for albinism does not make you lighter or different colored. You either are an albino, or you are not. That simple. Also, the trait can be carried for many generations without expression, then link up with another albinist gene, resulting in albino offspring and a shocked breeder. Other factors beside albinism can result in light-colored coats. Usually this is the result of a protein that blocks the formation of pigments, such as the seasonal "albinism" of northern mammals, like in the weasel, hare and fox. This is not true albinism, because the pigments still exist in the skin and eyes, and some of the fur, and they return with the next moult. Other times, animals can have a white or light colored coat, such as in the Black-eyed whites, and this trait can blend with other coat colors to form intermediates of some type. Again, these are not albinos, and the lack of pigment in the fur reflects changes in the genetics at a different location than for albinism. In fact, albinos can have the same genes as your typical sable, and would look like one if they could make the pigments. BTW, the eyes are red because you can see the red blood vessels on the retina (very vascular). The eyes of dead albinos turn white or light bluish. As I've already said, I am not sure of the exact genetics of ferret coloration, but I would expect fur coloration to be carried in 3 or more places. It would require a minumum of three different locations to explain the existing main colorations; sable, panda, and cinnamon. Some breeders will surely object to this simplification, but from what I've seen and read, all other "breeds" are in fact either variations or combinations of these three, excluding the albinos of course. Personally, I think fur coloration may turn out to be carried on even more than three locations, perhaps as many as five, but the extra locations are either close to one or more of the other locations so become linked to nearby traits. Which is why some colorations exhibit a high incidence of deafness or lowered mental abilities. (In humans, we see similar effects in blonds. Oooooo, a blond joke!) Occasionally, because of cross-overs or whatever, they throw off expectations and you get a different look than expected. (OK, I admit I did some nasty math to get to the figure of three locations. I would tell you how I did it, but then I would have to kill you...) Historically, I think the tendency was for albinos to be called ferrets, and sables, easily just as domesticated, to be called either fitch, fitch-polecat or polecat. Linneaus described an albino in setting up the ferret binomial, but I think he understood ferrets existed in many coloration schemes, and used the albino as a type species because he could be sure the breed was pure. They may not have had a clue about genetics in the 18th century, but they fully understood husbandry, and knew to keep albinos white. Linneaus knew ferrets were sometimes back-crossed with wild polecats to improve the hunting instincts, and wanted his type specimen to be a true representation of the ferret. Not long after Linneaus described the ferret, it was described in a British paper as having two coloration schemes, the red-eyed white, and the fitch, which was lighter and less masked than the polecat, a coloration scheme the still generally holds. Without a doubt, the ancestral coloration of the ferret was sable. No doubt, no argument. In fact, sable, or a very close variation, is ancestral to ALL members of the weasel subgroup, including mink, weasels, polecats, and ferrets, as well as most of the Mustelidae. During the domestication process and undoubtedly due to inbreeding, albinism developed, and was obviously selected for, perpetuating the trait. I cannot answer the question. "why did they want albinos?" because I wasn't there, there is a curious lack of archaeological evidence, and because the people who did it are long dead and they didn't write down their reasons. They just seemed to like albino ferrets, and you can speculate as to why, but any speculation is 100% pure storytelling. What would be very nice is for breeders to publish their "formulas" for obtaining certain colorations and breeds. With that type of data it would be fairly simple to determine the relationships between the various locations that control for coloration. Links, blending, dominance and other characteristics could be worked out for the ferts, and then breeders could make predictions and exploit the data for even more variations. My apologies if in simplification or condensation the genetics or breeding portions of this post are unclear. I will be happy to write much much more and send it privately. I also apologize for typos. For some reason, my server is randomly adding or deleting the occasional character. Pigmentally Challenged Bob C,12 Fitch of Color and 5 White Girls [Posted in FML issue 1917]