MITF (microphthalmia-associated transcription factor) tumor syndrome is a genetic syndrome that predisposes to the development of melanoma and renal cell cancer. Affected individuals have been found to have a particular missense mutation in the MITF gene (318 glu-to-lys) that has been reported to increase the risk of melanoma and renal cell cancer by up to 5 times that of the unaffected population. MITF is a transcription factor that is involved in cell cycle regulation; the mutation alters the transcription of MITF target genes.

Affected kindreds have been reported to have lighter skin phototypes, non-blue eye color, higher nevus count (mainly reticular pattern under dermoscopy), and onset of melanoma in those younger than 40 years. Some cohorts have demonstrated predominance of nevi greater than 5 mm in diameter, atypical nevi, multiple primary melanomas, and amelanotic melanomas. While some studies found an association with darker hair colors, others did not.