The interaction networks among GAL, GAP43, NRSN1 and our previous identified GABRG2, RELN and PTCH1 genes might be involved in the risk of HSCR, and specifically, the interactions between GAP43, NRSN1 and PTCH1 might confer the increased risk to HSCR. Here, GAP43 is linked to Hirschsprung disease.