DMPK and myotonic dystrophy type 1: Myotonic dystrophy type 1 (DM1) is a multisystem disease associated with an unstable expansion of nucleotide repeats (CTG [cytosine–thymine–guanine] triplets) in the genes coding for myotonic dystrophy protein kinase (DMPK) [1] that contribute to the accumulation of mutant RNA aggregates, with consequent mis-splicing of downstream effector genes that affect almost all cells and organs of the human body [2,3,4].