The first documented version of the pink-eyed dilution mutation is believed to come from Asia and today there are over 100 documented varieties. Some of them occurred due to spontaneous natural mutations while others were induced mutations by means of x-ray or chemical mutagens. The genes occur on chromosome 7 and its referred to as the P-locus (Brilliant, Ching, Nakatsu, and Eicher 1994). The version of P-locus gene that is present in the fancy mouse hobby is simply called “Pink-Eye Dilution” (p). This is reported to be the oldest and most common version of the gene (Silvers 1979).
A common feature among these P-locus genes is a reduction in coat color and eye color pigment. Depending on the version of the gene this effect can be minor or extreme. Although the pink-eye effect can appear similar to that of C-locus genes, such as albino or siamese, but the genes are different and occur at a different locus (The Finnish Mouse Club 2020, Brilliant, Ching, Nakatsu, and Eicher 1994).
The genotype for homozygous pink eye is “p/p” but this is always combined with other coat color genes and produces a variety of phenotypes (American Fancy Rat and Mouse Association 2019).
Another thing to keep in mind that different Fancy Mouse Clubs may use different terms to describe a phenotype even though the genotype may be the same. For example mice that have the pink-eyed black genotype (aa pp) may be referred to as Dove, Lilac (The Finnish Mouse Club 2020) or blue lilac (Silvers 1979). Conversely, sometimes a phenotype name may be used regardless of the mouses genotype (Fance Mouse Breeders Association 2020).
Some common phenotype names that involve the pink-eye dilution gene include Dove, Pink-eyed Dove, Lilac, Blue Lilac, Silver, Pink-eyed Blue, champagne, Cream, Chinchillated Dove, Lavender, Orange, Argente, Blue Argente, Argnete Creme, Pink-eyed Fawn, Cinnamon, Fawn, or White. Pink-Eye Dilution gene can also accompany any variety of marking such as pied, spashed, broken, hereford, head spot, rumpwhite, merle, roan or any variety of coat type such as nude, angora, texel, or frizzie (Fance Mouse Breeders Association 2020, Silvers 1979, The Finnish Mouse Club 2020, American Fancy Rat and Mouse Association 2019).
Brilliant, M., Ching, A., Nakatsu, Y, and Eicher, E. (1994) The Original Pink-Eyed Dilution Mutation (p ) Arose in Asiatic Mice: Implications for the H4 Minor Histocompatibility Antigen, Myodl Regulation and the Origin of Inbred Strains. Genetics, 138, 203-211
Silvers, W. (1979) The Coat Colors of Mice: A Model for Mammalian Gene Action and Interaction. Springer Verlag, Retrieved from: http://www.informatics.jax.org/wksilvers/index.shtml
American Fancy Rat and Mouse Association (2019) Fancy Mouse Genes, Alphabetical Name Listing, Retireved from: https://www.afrma.org/geneticsblackmse.htm
The Finnish Mouse Club (2020) P-locus. Retrieved from: http://www.hiiret.fi/eng/breeding/?pg=5&sub=7
Fancy Mouse Breeder’s Association (2020) Show Standards. Retrieved from: http://www.fmbamice.com/show-standards/