We present a PCR-based Mse I restriction fragment length polymorphism
(RFLP) in the promotor of the human CTLA4 gene at position -318 relati
ve to the ATG start codon. In a random caucasian population including
239 individuals the allele frequency of the polymorphism was 13.4%, wi
th a calculated heterozygosity rate of 23.2% and an observed one of 25
.1%. CTLA4 and CD28 are two genes in close proximity on the long arm o
f chromosome 2. Both of them influence T-cell activity in an antigen-i
ndependent way. They represent candidate genes for several immunologic
al disorders. Recently association between the CTLA4 gene and Graves'
disease has been shown. The Mse I RFLP in the CTLA4 promotor might ser
ve as a useful tool for further association studies. (C) 1996 Academic
Press, Inc.