Melanocytic nevi, or moles, are nonmalignant growths that arise from pigment producing cells of the skin. They are mostly found in sun-exposed areas; however, they also can be found in sun-protected areas, such as the palms, soles of feet and nail beds, where they are known as acral nevi. While the mutation profile of nevi in sun-exposed areas is well understood, less is known about the genes that are commonly mutated in acral nevi. And while a subset of melanoma of sun-exposed skin arises in nevi, the link between nevi and melanoma in acral skin is poorly understood. In a new study published in JAMA Dermatology, Moffitt Cancer Center researchers report on the mutation profile of acral nevi and describe differences between acral nevi and acral melanoma.