In other studies, we and others have shown that reductions in DMPK and SIX5 levels, which occur as a consequence of nuclear aggregation of the mutant DMPK RNA encoding CUGexp with the MBNL family of proteins and allele specific silencing of SIX5 expression resulting from CTG tract expansion respectively, are sufficient to result in a subset of DM1 cardiac, skeletal muscle, ocular and gonad pathologies10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20. Here, SIX5 is linked to myotonic dystrophy type 1.