Aims:

We propose to search for genetic risk factors shared between asthma (A), hayfever (H) and eczema (E) by performing a GWAS with cases defined by the presence of at least one of these three diseases (A+ or H+ or E+). Controls will be defined as individuals who are free of any allergic disease (A-H-E-). To compare the effect of individual variants on each disease per se, we will perform a secondary set of analyses, contrasting allele frequencies between the three mutually exclusive phenotypes A+H-E- (asthma only), A-H+E- (hayfever only) and A-H-E+ (eczema only).