Fig. 2

Mutant frequency in the lungs of gpt delta mice administered 1,2-NQ. Data used to estimate the total mutant frequencies is summarized in Additional file 4: Table S2. The frequencies of base substitutions (G-to-A transition, G-to-T transversion, or A-to-T transversion) were calculated by dividing the number of mutants in each animal (shown in Additional file 5: Table S3) by the total frequency (shown in Additional file 4: Table S2). Blue, green, red, and yellow lines show mutant frequency of total, G-to-A transition, G-to-T transversion, and A-to-T transversion. Symbols and bars indicate average values and SD. *P < 0.05