Since the MAPK pathway can be dysregulated due to activating mutations in NRAS, KRAS or BRAF in 40–50% of MM patients (25% NRAS, 25% KRAS and 4% BRAF), BRAF inhibitors such as vemurafenib and dabrafenib, and MEK inhibitors such as trametinib and cobimetinib are being evaluated. The gene discussed is KRAS; the disease is Miyoshi myopathy.