The development of sebaceous gland tumors in Fhit-deficient mice [64], a condition analogous to the sebaceous tumors of Muir-Torre syndrome in mismatch repair-deficient mice and humans [65], [66], and the observation that there are two forms of sebaceous tumors in humans, one form exhibiting mismatch repair gene deficiency and one exhibiting Fhit-deficiency [67], [68], can now be understood as a classic illustration of the caretaker function of Fhit. The gene discussed is FHIT; the disease is Muir-Torre syndrome.