Two types of somatic recombination are necessary for the generation of complete immunoglobulin heavy-chain genes

Abstract
At least 2 types of somatic recombination are necessary for the generation of a complete [mouse] immunoglobulin .gamma.2b gene from germ-line DNA sequences. The 1st type of recombination consists of the assembly of 3 separate DNA segments, each encoding a different part of the variable region. The 2nd type of recombination replaces the exons coding for the constant region of the .mu. chain with those coding for the same region of the .gamma.2b chain. The DNA sequencing studies suggest that the 2 types of recombination operate by different mechanisms.