Well I'm no expert on genetics of color, but I have a suggestion. Check out the literature on breeding canaries for color. Also check out mice breeding for color and coat characteristics. Jackson labs would be a good source of information on this. My recollection on canary coloring is that yellows come from a mutation in the melanin gene that leaves intact the other color genes such as eumelanin and one other that I can't remember. I used to own a corn snake with a coloring that made me think that it was mutant in its melanin gene because it was orange rather than brick red. Albinos in mice and cats traditionally have various neurological problems that stem from improper growth of certain sensory nerve tracts for example siamese cats (which are I believe a temperature sensitive form of albinism) have incomplete crossing over of their visual system that makes them appear cross-eyed. Steel mice (a black eyed white mouse) also have some visual system anomilies. Max [Posted in FML issue 1908]