CLDN18 and celiac disease: This included three genes involved in the formation and maintenance of tight junctions as well as those with direct ties to wheat allergies and Celiac Disease including tight junction genes cldn18 on LG3 and cldn34 and zgc:153311 on LG8 (Table 3) and rgs1 and scp2a also on LG3, which contained three markers within intronic regions (Table 3; Table S4).