In a panel of five colon cancer cell lines, RNAi-mediated TIMELESS depletion for 72 hours ubiquitously caused an increase in γH2AX, a marker of DNA damage (Fig 5); however, the cell lines demonstrated variable levels of H2AX phosphorylation with HCT15 cells resulting in a relatively small increase. The gene discussed is H2AX; the disease is malignant colon neoplasm.