ATRX and cancer: We analyzed the cell cycle profile of the ATRX-positive and -negative cancer cell line pair, HCT116 and HCT116 ATRXN/O, growing exponentially and asynchronously, and found similar cell cycle profiles (percentages of cells in the G1, S and G2/M compartments were 37.8±0.4, 28.1±0.3, 31.5±0.5 for HCT116 cells; and 34.4±0.5, 27.3±0.5 and 33.9±1.1 for HCT116 ATRXN/O cells; mean±s.e.m., n=3).