Organization and evolution of immunoglobulin VH gene subgroups.

Publisher Website
Google Scholar
Abstract
The organization and evolution of Ig variable region genes was studied by comparing human and mouse heavy chain variable region (VH) genes. A VH gene subgroup constitutes a physically linked multigene family separated from another VH subgroup. The VHIII gene subgroup was mapped to be 3'' to the VHII gene subgroup based on deletion of VH genes after V-D-J rearrangement. The human VHIII gene subgroup underwent a significant gene expansion as compared to the mouse VHIII subgroup. Human VHIII genes apparently correspond to only a small subset of mouse VHIII genes. Human VHIII genes contain a shorter intron and are 2 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.