Proceedings of the National Academy of Sciences · 1982 · 114 citations · 29 references
Life SciencesGeneticsMolecular GeneticsComparative GenomicsGenomicsMolecular EvolutionGene FamiliesGene MappingGenetic LinkageImmunoglobulin DiversityImmunoglobulin Gene RearrangementMammalian GeneticsBase SubstitutionsHeavy Chain Variable Region GenesImmunoglobulin Gene SegmentsImmunoglobulin Gene VariationImmunoglobulin Heavy Chain RearrangementMultigene FamiliesMultigene Family ExpansionSubstitutions
The organization and evolution of immunoglobulin variable region genes was studied by comparing human and mouse heavy chain variable region (VH) genes. We show that a VH gene subgroup constitutes a physically linked multigene family separated from another VH subgroup. We mapped the VHIII gene subgroup to be 3' to the VHII gene subgroup based on deletion of VH genes after V-D-J rearrangement. The results indicate that the human VHIII gene subgroup underwent a significant gene expansion as compared to the mouse VHIII subgroup. Amino acid sequence data indicate that human VHIII genes correspond to only a small subset of mouse VHIII genes. Human VHIII genes contain a shorter intron and are two codons shorter than most BALB/c mouse VHIII genes. The nature of nucleotide substitutions between VH genes within a species (human) is similar to that between genes of different species (human/mouse). Both contain approximately 50% silent substitutions.
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