Heh! I want!! Fly over here please 
Rex is on chromosome 11 and hairless is on chromosome 14. They're inherited independently of each other, and in different manners (one is dominant; the other is recessive).JustMouse said:I'm pretty sure that rex and hairless are closely related.
All mice do this, actually. It is called molting, and some do it a lot more than others. Each new coat can sometimes be very different in color or texture. You just don't notice it much on standard coated mice or well-bred non-standard coats. This is why most mice at professional shows are standard (or satin) and why most show breeders stay away from fuzzy, rex, and angora coats. There's just too much variability.But also, they seem to randomly lose, and re-grow hair through out their lives.