The invention is directed to a hairless, immunodeficient mouse that ishomozygous recessive for a hairless (Hr hr)allele and both B-cell deficient and T-cell deficient. The B-cell and T-celldeficiency is attributed to a homozygous recessive scidallele (Prkdc scid) a homozygous recessive beige allele (Lyst bg), or amutated Rag allele. These mice offer an advantage over nudemouse models used in cancer research because they can be maintained ashomozygous breeding pairs and they have greater immunedeficits, which permit better growth of xenogenic tumor lines, and rapidassessment of cutaneous and subcutaneous tumorsand tissue grafts.
