To confirm these results, and to ensure that the effect of autophagy inhibition on tumor incidence was not due to unintended consequences of transgene genomic insertion, we generated an independent transgenic line in which the mitfa promoter drives expression of a dominant-negative form of the autophagy protein Atg4b [Tg(mitfa:atg4bC74A)]. The gene discussed is MITF; the disease is neoplasm.