The subject invention pertains to a method of detecting colon disorders including inflammatory bowel disease, such as Crohn's disease and ulcerative colitis, based on underexpression of Lipopolysaccharide Responsive Beige-like Anchor (LRBA). Advantageously, the invention may be used to test for inflammatory bowel disease using a blood sample from a subject before a more invasive test for colon disorders is employed. The invention also pertains to methods of treating a colon disorder in a subject in which the colon disorder is detected.