Abstract
The genetic contro of the expression of an idiotype (Id-460) associated with the 2,4-dinitrophenyl (DNP)-binding BALB/c myeloma protein MOPC 460 was studied using congenic strains of mice. It was shown that the expression of high levels of Id-460 during secondary in vivo anti-DNP-ovalbumin responses was determined by genes governing immunoglobulin heavy-chain variable and kappa-light chain variable regions (V kappa). Appropriate alleles at both loci were required for the expression of Id-460. Genes in the major histocompatability complex and the X-linked immune deficiency gene found in strain CBA/N did not greatly affect Id-460 expression. The V kappa gene controlling Id-460 expression can be differentiated from Lyt-3, and it is the first instance in which expression of an idiotype subdivides the V kappa genes associated with the Lyt-3a allele. Although it is likely that the V kappa gene(s) involved are structural, the involvememt of a regulatory gene linked to the structural gene can not be excluded.