severe combined immunodeficiency disease

severe combined immunodeficiency disease
    n 1: a congenital disease affecting T cells that can result from
         a mutation in any one of several different genes; children
         with it are susceptible to infectious disease; if untreated
         it is lethal within the first year or two of life [syn:
         {severe combined immunodeficiency}, {severe combined
         immunodeficiency disease}, {SCID}]