IL4 and allergic disease: The first, examining eczema followed by asthma within the framework of the atopic march, identified five loci previously associated with at least one allergic disease (FLG, IL4/KIF3A, AP5B1/OVOL1, C11orf30/LRRC32, and IKZF3) and two novel loci specific to the eczema–asthma phenotype (EFHC1 and TMTC2) [16].