With these data sets we identified three loci that are of genome wide-significance in the combined analysis of the Icelandic and Danish samples; intronic variants at the ARHGAP15 and COLQ loci associate significantly with diverticular disease and at FAM155A locus with diverticulitis (P<2.3 × 10−9, the threshold for intronic variants within a DNase hypersensitivity site12) (Table 1 and Supplementary Table 3). This evidence concerns the gene ARHGAP15 and diverticulitis.