Therefore, the main objectives of this study were to evaluate the nuclear profile in DM1 patient-derived and control fibroblasts and to determine the intracellular protein levels and immunolocalization of the disease-associated DMPK protein and other NE proteins, namely lamin A/C, emerin, lamin-associated polypeptide 1 (LAP1), Sad1/unc-84 protein-like (SUN1), nesprin-1 and nesprin-2, in both cell lines. The gene discussed is SUN1; the disease is myotonic dystrophy type 1.