Scid mouse

Severe Combined Immunodeficiency Disease - Immunodeficiency Disease or SCID mice cannot make T cells or B cells. Thus they are helpless not only to fight infection but also to reject transplanted tissue. This is due to exceedingly rare and useful recessive mutation on chromosome 16 responsible for deficient activity of an enzyme involved in DNA repair (in the Prkdc or "protein kinase, DNA activated, catalytic polypeptide" gene). Because V(D)J recombination does not occur, the humoral and cellular immune systems fail to mature. SCID mouse is therefore one of the best animal models ever found for studying the basic biology of the immune system as well as several diseases. They have been extensively used as hosts for normal and malignant tissue transplants. In addition, they are useful for testing the safety of new vaccines or therapeutic agents in immunocompromised individuals.

Severe Combined Immunodeficiency Disease occurs in humans as an autosomal recessive trait or X-linked characteristic that is clinically very similar to the mouse scid mutation. A clinically similar disease also occurs in Arabian foals.