Altogether, the authors proposed that the hypermethylation of CTCF-binding sites leads to DM1 locus transcriptional dysregulation with a consequent decrease of antisense CAG siRNAs and increase of expanded (CUG)n-mediated toxicity, whose downstream effects lead to muscle deficiencies in congenital DM1 [198] (Figure 2). Here, CTCF is linked to myotonic dystrophy type 1.