The RAS pathway plays a main role in switching of MGUS to MM, since activating RAS mutations (mainly neuroblastoma ras viral oncogene homolog (NRAS) or v-ki-ras2 kirsten rat sarcoma viral oncogene homolog (KRAS)) are found in 32–50% of patients with MM [20]. This evidence concerns the gene KRAS and Miyoshi myopathy.