Although MBNL1 colocalized with both C/CUGexp-RNA aggregates, the extent of sequestered MBNL1 and subsequently, the levels of remaining free and functional protein may be different in DM1 and DM2 cells, particularly if the dynamics of accumulation of MBNL1 into CUGexp- and CCUGexp-RNA aggregates is not the same. Here, MBNL1 is linked to myotonic dystrophy type 1.