Importantly, recent studies using a panel of preterm transgenic mice coexpressing epidermis-targeted coexpression of MCPyV ST and the cell fate determinant atonal bHLH transcription factor 1 (ATOH1) led to the development of widespread cellular aggregates, with histology and marker expression mimicking human intraepidermal MCC, supporting the concept that ST is the major MCPyV-derived oncogenic driver in MCC (40). This evidence concerns the gene ATOH1 and Merkel cell skin cancer.