Epidermal, sebaceous, and melanocytic nevoid proliferations are spectrums of mosaic RASopathies.

Growing evidence demonstrates that various nevoid proliferations such as keratinocytic epidermal nevi and nevus sebaceous result from somatic mosaicism. Many of the mutations identified have been within the RAF/RAS/MAPK pathway, hence supporting the previously introduced term "mosaic RASopathy" for these nevi. In this issue, Kinsler et al. were among the first to characterize certain pigmented melanocytic nevi that may also fit this paradigm. To better frame these findings, we provide a summary of the analogous genotypic profiles for epidermal and melanocytic nevi from recent studies.