Since severe constipation and other GI symptoms are common phenotypes in patients with WDSTS, we stained the distal colon sections of Kmt2a+/+ and Kmt2a+/LSL mice for Calretinin, a clinical diagnostic marker for Hirschsprung’s disease (HD) that marks ganglion cells (18). This evidence concerns the gene CALB2 and Wiedemann-Steiner syndrome.