Several MEK inhibitors are used clinically, with trametinib, cobimetinib and binimetinib being approved for BRAF-mutant melanoma [30], while selumetinib is also approved for use in children with neurofibromatosis type 1, an example of MEK inhibitor efficacy in tumours with RAS pathway perturbation that is not in RAS itself [31]. This evidence concerns the gene MAP2K7 and neurofibromatosis type 1.