SEMA3D encodes a member of the semaphorin III family of secreted signaling proteins involved in axon guidance during neuronal development and is one of the three signaling pathways of HSCR pathogenesis (Luzón-Toro et al., 2013; Jiang et al., 2015; Kapoor et al., 2015); the other two are RET and EDNRB signaling pathways (Amiel et al., 2008; Tilghman et al., 2019). Here, RET is linked to Hirschsprung disease.