The NF-κB pathway participates in apoptosis, differentiation and proliferation of cells, immunity, inflammation, and lymphopoiesis, is affected in 40% of MM cell lines and 12–20% of MM patients, and is represented by mutations mostly in TRAF2, TRAF3, CYLD, NFKB2, NFKBIA, and LTB genes [28,82,86,328,399,400]. The gene discussed is NFKBIA; the disease is Miyoshi myopathy.