Analysis of conventional CRC locations (right and left) and our proposed CRC locations (proximal/distal and middle) showed that AA patients had significantly higher frequency of KRAS mutations than white patients both in left colon (51.9% vs. 10.7%, p<0.001) and in proximal/distal colon (55.9% vs. 26.4%, p<0.001) (S3 Table). The gene discussed is KRAS; the disease is colorectal carcinoma.