In the combined Icelandic and Danish data sets we observe significant association of intronic variants in ARHGAP15 (Rho GTPase-activating protein 15; rs4662344-T: P=1.9 × 10<sup>-18</sup>, odds ratio (OR)=1.23) and COLQ (collagen-like tail subunit of asymmetric acetylcholinesterase; rs7609897-T: P=1.5 × 10<sup>-10</sup>, OR=0.87) with diverticular disease and in FAM155A (family with sequence similarity 155A; rs67153654-A: P=3.0 × 10<sup>-11</sup>, OR=0.82) with diverticulitis.