DDX39A and amyotrophic lateral sclerosis: Using ALS patient-specific induced pluripotent stem cell (iPSC) models, Patani et al. further unveiled that the four abnormal accumulated sequence-specific intron retention transcripts (IRTs) in VCP mutations included SFPQ, OGT, TUSC3, and DDX39, and their binding affinity to RNA binding proteins (RBPs) could be the key attributes for RBP localization (73, 74).