Among the 13 patients with anti-HMGCR autoantibodies when classified according to the ACR/EULAR criteria from 2017, eight (62%) were as polymyositis and five (38%) as dermatomyositis with typical skin manifestations: Gottron’s sign (30%), Gottron’s papules (15%), heliotrope rash (15%), V-sign (8%), or periungual lesions (23%). The gene discussed is HMGCR; the disease is dermatomyositis.