GENETIC-LINKAGE OF T-CELL RECEPTOR ALPHA DELTA COMPLEX TO SPECIFIC IGE RESPONSES/

IgE responses to inhaled proteins underlie the clinical syndrome of al lergic (atopic) asthma and rhinitis. We have investigated genetic link age between specific IgE reactions to highly purified major allergens and the T-cell receptor (TCR) alpha: and beta gene complexes on chromo some 14 and 7, respectively. Antigens tested included highly purified proteins from the housedust mite Dermatophagoides pteronyssinus, the d omestic cat and dog, grass pollen, and the mould Alternaria alternata. Affected sibling-pair methods were used in two independent sets of fa milies, one in the UK and one in Australia, No linkage of IgE serotype s to TCR-beta was detected, but significant linkage to TCR-alpha was s een in both family groups, For several of the IgE phenotypes investiga ted (positive responses to whole allergen sources or purified antigens or serum IgE above the 70th percentile in the population) the affecte d sibling-pairs showed significant sharing of TCR-alpha microsatellite alleles from both parents. The results show that a gene (or genes) in the TCR-alpha region modifies specific IgE responses.