In addition, IHC revealed that the protein level of HIF‐1β was markedly increased in bone marrow biopsies of MM patients, particularly those carrying 1q21 gain, compared to healthy donors (Figure 2A, right; inset, FISH for detection of 1q21 gain; the representative areas shown are indicated by square in Figure S2A). The gene discussed is ARNT; the disease is Miyoshi myopathy.