Immune response and disease resistance in chickens. II. Marek's disease and immune response to GAT.

Genetic control of resistance of susceptibility to Marek's disease in chickens was found to be associated with immune response to the amino acid polymer GAT. Thus, both B1B1 and B19B19 GAT low responders had significantly greater incidence of MD than the B1B1 and B19B19 GAT high responder counterparts. The results point to gene(s) controlling MD resistance mapping within the immune response region of the B complex, the major histocompatibility system of the chicken. Patterns of general mortality demonstrate that the low viability, observed over several years among B1B1 birds, likewise is associated with the immune response region of the B complex.