Altered nucleic acids of antibody-forming tissues

RNA.DNA hybridization experiments suggest differences between the DNA from the liver and spleen of the same animal (rabbit) and between the RNAs from lymph nodes stimulated by different antigens. A larger proportion of spleen DNA than of liver DNA was complementary to the RNA isolated from antigen-stimulated lymph nodes. No difference between liver and spleen DNA was observed in hybrids formed with RNA from lymph nodes of nonimmune animals. This suggests the presence of unique or redundant genes coding for immunoglobulin polypeptide chains in antibody-forming cells.