The DMPK locus harbours three more CpG islands, one in the neighbouring myotonic dystrophy WD repeat containing (DMWD) gene, CpGi 74, and two in the DMPK gene, namely CpGi 43 and 36; however, nothing is known about the epigenetic state of these CpG islands in DM1. The gene discussed is DMPK; the disease is myotonic dystrophy type 1.