Human T-cell receptor beta-chain genes

cDNA clones encoding the beta chain of the T-cell antigen receptor from the human leukaemic cell line JM (which extend through the constant region and into the variable region of the receptor) show hybridization only to RNA from JM cells, and not in five other T-cell leukaemias. Multiple hybridizing bands were detected in genomic DNA digests by a V beta probe, suggesting that inherited V beta gene diversity will be significant. Two beta-chain constant region genes (designated C beta 1 and C beta 2) occur in human genomic DNA, and both of these genes are capable of rearrangement in T-cell DNA. When the downstream C beta 2 gene is rearranged, deletion of the C beta 1 gene can occur. These characteristics of rearrangement and deletion of beta-chain genes show analogies to the immunoglobulin gene loci.