TRIM33 and myositis disease: In a nationwide study on the prevalence of MSAs in the Netherlands (Euroline myositis line-blot assay; Euroimmun), out of 88 patients with an MSA, 49% of MSAs were DMSAs, with relative proportions ranging between 15% (anti-TIF1-γ) and 2% (anti-SAE-1) [81].