title: Intergenic exchange maintains identity between two human lambda light chain immunoglobulin gene intron sequences.
abstract: Evidence for gene conversion or unequal double crossover in the human lambda light chain immunoglobulin locus is presented. The high level of J2C2-J3C3 intron cross-hybridization, the identity of the J lambda and J lambda 3 coding and intron sequences, the presence of multiple base differences between the C lambda 2 and C lambda 3 coding regions, and the presence of both the unconverted and converted alleles in the normal gene pool, suggest that a recombinational event has resulted in the conversion of the J lambda 2 coding and intron sequences to those of J lambda 3 and its flanking sequences. Intergenic exchanges, such as the one described here, may provide a mechanism to maintain sequence homogeneity and functionality among the duplicated members of the human lambda gene family.
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D005785:Gene Conversion; D005803:Genes, Immunoglobulin; D005854:Germ Cells; D006801:Humans; D007144:Immunoglobulin J-Chains / Q000235:genetics; D007146:Immunoglobulin lambda-Chains / Q000235:genetics*; D007438:Introns; D007668:Kidney / Q000378:metabolism; D008969:Molecular Sequence Data; D005810:Multigene Family; D009693:Nucleic Acid Hybridization; D011110:Polymorphism, Genetic
chemical_list: D007144:Immunoglobulin J-Chains; D007146:Immunoglobulin lambda-Chains