MORC3 and dermatomyositis: There are five myositis-specific antibodies (MSAs) in DM, including anti-transcription intermediary factor 1-γ, anti-complex nucleosome remodeling histone deacetylase, anti-melanoma differentiation gene 5, anti-nuclear matrix protein 2 (NXP2), and anti-small ubiquitin-like modifier-activating enzyme (1, 2).