Gene(s) affecting the expression of Qa-1

Lymphocytes from different strains vary in their expression of antigenic determinants encoded by the Qal locus. Thus, a lower percentage of cells from strains bearing H-2D^k are lysed in antibody-mediated cytotoxic tests. These cells fail to completely absorb anti-Qal activity from antisera. The unexpressed determinants are present in unactivated cells when subcellular fractions are tested and are detectable on the membrane of mitogen-activated lymphocytes. The gene(s) controlling this phenomenon are dominant and map to a region between H-2S and Tla.