HtrKid said:
Okay so i was just looking at rat genetics and am wondering if you can get hairless from rex. For rats you can breed 2 double rexes together and get hairless or fuzzy. Is that true for mice?
No... for rats that's not how it works.
You cannot breed 2 doublerexes and get hairless or fuzz.
Fuzz (fzfz) is a different gene than rex (Rere). A Doublerex (ReRe) is just a rat with 2 rexgenes.
The rexgene is a dominant gene - fuzz is a recessive gene (the same with both rats and mice).
If you breed 2 doublerexes, you will get 100% doublerex in the litter, if the parents don't have other genes in comment - eg the fzfz gene.
If both parent are ReRe Fzfz, you will get 75% doublerex and 25% fuzz (in theory).