CSNK1A1 and small intestine carcinoma: In fact, it has been observed that small molecule-mediated activation of CK1α decreases proliferation[25] whereas targeted deletion of CK1α, when combined with p53 or p21 deletion, enhances proliferation resulting in small bowel carcinoma.[26] It is possible that the D163N mutation characterized in patient 815zp led to enzymatic inactivation of CSNK1A1 and ultimately promoted, perhaps when combined with other mutation(s), the development of colon cancer.