The transporter protein encoded by the ABCC4 gene is implicated in resistance to 5-Fluorouracil in pancreatic cells (https://www.pharmgkb.org/ accessed on 22 June 2022), a principal drug employed in colorectal cancer treatment, and although the protein produced by the NAT1 gene is not involved in metabolism of colorectal cancer chemotherapy, it participates in the mesalazine catabolism pathway (https://www.pharmgkb.org/ accessed on 22 June 2022). The gene discussed is NAT1; the disease is colorectal cancer.