SIX5 and myotonic dystrophy type 1: A prime example is observed at a CTG repeat in the 3’UTR of the DMPK gene associated with myotonic dystrophy type 1 (DM1), expansion of which alters local chromatin structure and suppresses transcription of neighboring gene, Six5 (Winchester et al., 1999; Brouwer et al., 2013; López Castel et al., 2011).