title: Organization and evolution of a gene cluster for human immunoglobulin variable regions of the kappa type.
abstract: An 80,000 base-pair region from the gene locus encoding the variable regions of the human immunoglobulins of the kappa type (V kappa genes) was cloned and analysed. The region comprises five V kappa sequences of subgroup I and one interspersed V kappa pseudogene of subgroup II. The six genes and pseudogenes are arranged at different distances but in the same orientation. The organization of the cluster can be explained by a series of amplification steps; the existence of a V kappa II pseudogene in a V kappa I gene cluster may have been the result of a transposition event; a final duplication step led to a second closely related copy of the cluster. From sequence data for altogether 16,000 base-pairs it appears that gene conversion-like events and subsequent selection contribute to both homogeneity and diversity of the V kappa repertoire.
mesh_terms: D000595:Amino Acid Sequence; D000916:Antibody Diversity; D001482:Base Composition; D001483:Base Sequence; D005075:Biological Evolution; D002874:Chromosome Mapping; D004262:DNA Restriction Enzymes; D005784:Gene Amplification; D005796:Genes; D006801:Humans; D007147:Immunoglobulin Light Chains / Q000235:genetics*; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D007145:Immunoglobulin kappa-Chains / Q000235:genetics*
chemical_list: D007147:Immunoglobulin Light Chains; D007135:Immunoglobulin Variable Region; D007145:Immunoglobulin kappa-Chains; D004262:DNA Restriction Enzymes