Recombination between kappa chain genetic markers and the Lyt-3 locus

Abstract

Recombination has been detected for the first time between chromosome 6 loci controlling kappa chain expression in normal mouse serum immunoglobulin and the Lyt-3 locus. The recombination event occurred at the 26th or 27th backcross generation during the derivation of the Lyt-2 ^a, Lyt-3 ^a-congenic line B6.PL(85NS). The line is now homozygous for the Lyt-2 ^a, Lyt-3 ^a allele(s) at N30F13 and homozygous animals express the Igk-Ef1 ^b allele derived from C57BL/6. The frequency of recombination has been estimated to be 0.30% based on the present results and previous studies in which no recombination was detected. The results rule out the hypothesis that the Lyt-3 locus itself controls the light chain phenotype observed in normal serum immunoglobulin.