We began these studies using C57BL/6J (B6) wild‐type (wt) mice that are naturally resistant to skin cancers (http://www.informatics.jax.org/mtbwi/tumorFrequencyGrid.do); we included (Fhit, murine fragile histidine triad gene) Fhit−/− mice on the B6 background, because Fhit (human or mouse protein) loss has been reported for skin SCCs 18, 19. Here, FHIT is linked to skin cancer.