A new polymorphic marker of the T-cell antigen receptor alpha chain genes in man.

The restriction fragment length polymorphism of the unrearranged T-cell antigen receptor (Tcr) alpha chain gene was investigated. Taq I digests, when probed with a Tcr alpha chain cDNA probe, revealed polymorphic bands of 7.0, 2.0, and 1.4 kb, due to variations around the C alpha gene, and the V gene cluster. Family studies confirmed the segregation of these polymorphic bands as allelic markers. These polymorphisms provide a new marker for the analysis of genetic variation of the Tcr alpha chain, and the influence of variation of the Tcr genes on the immune response.