Detection of a frequent restriction fragment length polymorphism in the human T cell antigen receptor beta chain locus. A potential diagnostic tool.

Abnormal T cell function is a feature of a spectrum of inherited and acquired diseases. We have detected a frequent restriction fragment length polymorphism in the human T cell antigen receptor beta-chain locus that may aid in the analysis of these disorders. A study of a panel of 18 normal individuals, testing for the presence of the polymorphism, showed it to account for 36% of the alleles in that group. In view of the fact that the T cell receptor beta-chain locus has been mapped to chromosome 7, and that the disease ataxia telangiectasia (AT) is associated both with abnormal T cell function and with chromosomal abnormalities of the same region of chromosome 7, we investigated the possibility that the polymorphism could demonstrate linkage of the T cell receptor locus to the gene for that disease. We demonstrated that the mutation causing AT did not lie within the beta-chain locus itself, and that there was preliminary evidence that the two loci were not closely linked. This polymorphism may provide a useful tool for the study of other genetic disorders associated with abnormalities of T cell function, as well as disorders associated with inherited or acquired abnormalities of chromosome 7.

Images.

Click on an image below to see the page. View PDF of the complete article

page 1283

page 1284

page 1285