Coding region polymorphisms of human T-cell receptor V beta 6.9 and V beta 21.4.

Two new TCRV beta coding region polymorphisms were identified: V beta 6.9a/b and V beta 21.4a/b. In both cases, a single nucleotide difference gives rise to an amino acid exchange. Genomic typing by the PCR/sequence-specific oligonucleotide probing technique was performed to study a possible contribution of these two new polymorphisms in susceptibility to autoimmune diseases. However, there was no association with insulin-dependent diabetes mellitus, rheumatoid arthritis, juvenile rheumatoid arthritis, multiple sclerosis, myasthenia gravis or coeliac disease. On the other hand, significant differences were found between Caucasoid and Oriental populations in frequencies of the V beta 6.9 and V beta 21.4 alleles.