Mosaic, pathogenic KRAS variants have previously been reported to cause a range of epidermal nevus syndromes, including encephalocraniocutaneous lipomatous syndrome (ECCL) (MIM 613001), nevus sebaceous syndrome (NSS) (MIM 163200), and oculoectodermal syndrome (OES) (MIM 600268), as well as Gorham-Stout disease, a subtype of CLA (7–13). Here, KRAS is linked to epidermal nevus syndrome.