We investigated the downstream consequences of RNA foci and have identified that sequestration of RNA splicing factors, MBNL1 and MBNL2 (Figure 3), in addition to abnormal patterns of alternative splicing were detectable in a repeat expansion-specific manner (Figure 4). These observations reinforce the notion that such RNA structures induce toxic gain-of-function effects that are likely to be disrupting overall cellular homeostasis, implicating aberrant RNA metabolism in the pathogenesis of CTG18.1-associated FECD.15, 37 Furthermore, these data demonstrate that these events are specific to CTG18.1-mediated FECD and are not a general downstream consequence of the disease, given that CECs derived from FECD-affected case subjects without expanded copies of the repeat did not display features of aberrant RNA metabolism.