CERS2 and gastrointestinal stromal tumor: Although to our knowledge none of these genes have been implicated in GIST tumorigenesis, ceramide synthase 2 (CERS2) has recently been implicated in breast cancer (reviewed in [44]), while endothelin 3 (EDN3) has been shown to play a role in melanocyte differentiation, and altered endothelin signaling may be involved in melanomagenesis or progression [45].