Domain structures of cell surface glycopeptides encoded by class I and class II beta genes of the major...

Published sequence data of MHC genes, cDNAs and MHC products were analyzed for their sequence homologies. Alignment statistics revealed that class I gene products consist of four mutually homologous domains, and that class II beta gene products is composed of three mutually homologous domains. Not only extracellular domains but also newly discovered C-terminal shorter domains of class I and class II beta gene products were found to have evolved from a one-domain-long beta 2-microglobulin-like protein by repeated exon duplications and splittings.