Finally, the overexpression of Drosophila CELF1 ortholog Bru3 and attenuation of MBNL1 counterpart mbl (Picchio et al, 2018; Auxerre‐Plantié et al, 2019) offer further valuable models for identifying gene deregulations underlying DM1. Here, MBNL1 is linked to myotonic dystrophy type 1.