Variation and Homology in the Mu and Gamma Heavy Chains of Human Immunoglobulins

Abstract
Sequence analysis of an 1gM immunoglobulin shows that the variable regions of hunman µ and γ1 heavy chainis may have twice as much homology as their constant regions and that evolutionary divergence of µ and γ1 heavy chain genes occurred not long after the separation of heavy and light chain genes.