The evaluation of the clinical potential of ERBB2/HER-2 targeting therapeutics, including monoclonal antibodies trastuzumab and pertuzumab, antibody-drug conjugates trastuzumab emtansine and trastuzumab deruxtecan, and small molecule TKI tucatinib alone and in combination with standard anti-MM drugs, as well as ERBB1-targeting antibodies and TKI, would seem warranted. Here, ERBB2 is linked to Miyoshi myopathy.