Heavy and light polypeptide chains isolated from different specific antibodies to haptens and from (gamma)G-immunoglobulin of normal rabbits have been resolved into distinct, multiple components by disc electrophoresis in polyacrylamide gels in the presence of urea. In spite of the resolution of these chains into multiple bands, different specific antibodies and normal rabbit (gamma)G-immunoglobulin were indistinguishable from each other by this method.