Coats & Misc.
For more rat genetics, see the
AFRMA Rat Genetics book,
specific articles listed with the various standards descriptions,
and the articles on the Info Pages: Breeding – Colors/Genetics –
Rat Genetics, part 1,
Rat Genetics, part 2,
Rat Genetics, part 3.
See also the Rat Biology articles
Where do different rat coat types come from?,
The hairless hr mutation,
The dumbo rat mutation and human analogues
See the AFRMA Rat Color Standards book and the Standards pages for photos.
Go to Fancy Rat Genes, Alphabetical Name Listing for a complete list.
See also Fancy Rat Genes, Genetic Code Listing for breakdowns by genetic code.
|Coats & Misc.|
|Bristle Coat||Br (code given by AFRMA)|
|Dumbo||dmbodmbo (ear/skull gene)|
|Essex||Hro++ or Hro++H (color fading gene; has Berkshire markings but breeds as a Self)|
|Fuzzy||fzfz or frH|
|Hairless||hrhr or fzfz|
|Hairless: CR (Charles River)||frCR|
|Nude||rnurnu (Rowett nude)|
|Odd-Eye||oe or ? (has 2 different colored eyes; usually pink/black but can be ruby/black or pink/ruby)|
|Roan (Husky)||? (recessive; roan gene lightens color with each moult till rat is nearly white; always in Berkshire or Berkshire Blaze markings)|
|Roan: Striped||? (recessive; a.k.a. Banded Husky)|
|C: Albino Locus (Burmese)+ (codes by Nichole Royer)|
|C||Full color (no dilution)|
|c||Albino (Pink-Eyed White)|
Note: Many rat colors/varieties have not been studied by geneticists so codes are given by fancy rat genetics experts or are unknown
Note: Capital letter=dominant genes unless otherwise noted; lower case letter=recessive genes
“–” means that either the dominant or recessive allele could occupy that space without affecting the outcome
* = g or Me or Dal code by Nichole Royer
** = Cscs Fyfy code by Ann Storey, N.F.R.S.
+ = ce or ci code by Nichole Royer
++ = Hro code by Sheila Sowter, N.F.R.S.
? = genetics unknown