For example, in the neuromuscular disorder Myotonic Dystrophy Type 1 (DM1), an expansion of CTG repeats in the 3'UTR of the Dystrophia Myotonica Protein Kinase (DMPK) gene results in retention of CUG-containing DMPK mRNAs within specific RNA foci in the nucleus. Here, DMPK is linked to myotonic dystrophy type 1.