The stool DNA test is a noninvasive laboratory test that identifies DNA changes in the cells of a stool sample. The stool DNA test specifically looks for DNA alterations associated with colon polyps and colon cancer.The major goal of the stool DNA test is to detect whether DNA changes that indicate colon cancer or precancerous polyps are present in the colon.One stool DNA test (Cologuard) is approved for use the United States.