Variants of endothelin-1 and its receptors in atopic asthma

Endothelin-1 (ET-1) is a 21 amino acid peptide released from several types of bronchial cells. It operates through two types of receptors, type A(ET-R A) and type B(ET-RB) and has various activities in the pathophysiology of a topic asthma, These genes are localised on different chromosomes where geno me-wide searches have identified linkage for atopic asthma, thus supporting the candidacy of ET-1 and its receptors for atopic asthma. A genetic assoc iation study was performed with variants of these three genes in both Briti sh (n = 300) and Japanese populations (n = 200), No significant association was found between variants of EDN1 and EDNRB genes, and atopic asthma in e ither population. However, variants of EDNRA gene showed a marginal associa tion with atopy [odds = 0.39(95% CI: 0.17-0.89), p = 0.022, Pc = 0.066], es pecially with antigen specific IgE levels [odds = 0.31 (95% CI: 0.20-0.77), p = 0.006, Pc = 0.018] in the British population. These findings suggest t hat EDNRA is a major candidate locus for atopy on chromosome 4. (C) 1999 Ac ademic Press.