Hair Types  Standard - standard is recessive to Rex, Double Rex, Velveteen, and Double Velveteen    Rex  [Re/re] - should have nice curles like a sheep. *[re/re] = standard coat *[Re/Re] = Double Rex    Velveteen - [Cu/cu] -also known as Valour- the look should be plush *[cu/cu] = standard coat *[Cu/Cu] = Double Velveteen    Satin    Harley    Double Rex [Re/Re] The fuzziness of Double Rex varies a great deal. 'Hodge Podge' has so little fuzz that he nearly looks hairless. *Homozygous Rex, known as Double Rex, will result in the hair breaking off resulting in varying degrees of baldness. Most breeders find this look very undesirable and choose not to breed for them. Other breeders claim that breeding a Double Rex [Re/Re] to a standard haired rat [re/re] result in favorable rex coated offspring. *Many pet stores and commercial breeders pass off Double Rex rats as Hairless.    Double Velveteen [CuCu] Same effect as Double Rex    Hairless (hr/hr) there are several genes that can cause hairlessness. 'Skinny' is hr/hr *[Hr/hr] = Standard hair carrying hairless *[Hr/Hr] = Homozygous Standard Hair