As mentioned before, (CTG)n repeats are part of a CTCF-dependent insulator located between DMPK and SIX5 genes [37], and this could place the CTCF binding sites in an internucleosomal accessible position at DM1 locus [37], supporting the idea of a more compact chromatin structure in this region [54]. Here, SIX5 is linked to myotonic dystrophy type 1.