Correlation between fragmented immunoglobulin genes and heavy chain deletion mutants

Abstract
It is generally accepted that the variable (V) and constant (C) regions of immunoglobulin (Ig) chains are under separate genetic control1. The notion that the different domains and interdomain regions are also under the control of independent genetic units was initially based on the clearcut results obtained by studying the primary structure of deletion mutants2–9 and received definitive support from direct analysis of cloned heavy (H) and light (L) chain genes10–13. Here we present additional studies carried out on two selected γ3 deletion mutants which indicate that the genetic control of human H chains may be even more complex than previously believed.