Figure 2

ENU-induced mutation frequency and spectrum. (a) The ENU-induced mutation frequency differs in time. Red circles indicate the mutation frequency of the F1 progeny of the 5 different msh6^-/-founders treated with 30 mg ENU/kg. The black stripes indicate the mutation frequency of all the F1 progeny of these founders together for the different time bins. A decrease of mutation frequency is observed in time, which reaches a steady level at 1.0 × 10^-6 per bp (1 mutation per 1 Mb). The letter n indicates the number of total F1 screened per time bin. (b) ENU-induced mutation spectrum in Msh6-deficient background (white bars) compared to MMR-proficient animals (black bars).