RBFOX1 and myotonic dystrophy type 2: However, when the ratio of CNBP/MBNL1 is examined, this correlation is lost, perhaps because of the involvement of additional RBPs such as RBFOX1/2 in DM2 pathogenesis (16), although RBFOX1 and RBFOX2 have similar expression profiles to MBNL1 across muscles, perhaps indicating yet unknown mechanisms of susceptibility.