Increased basal serum trptase levels were seen in 16% (15/92) subjects with EGID but <1% (1/143) of patients with atopic dermatitis with eosinophilia. Of the 15 subjects with EGID, 4 patients were found to have HαT as cause of elevated basal tryptase. This evidence concerns the gene TMPRSS11D and Increased total eosinophil count.