In conclusion, the single nucleotide polymorphisms in SIP1 gene rs41292293, rs34961586 and rs13017697 are associated with the ectopic expression of this gene in human HSCR and contribute to the susceptibility of this disease in population.
Although mutations in eight different genes (EDNRB, EDN3, ECE1, SOX10, RET, GDNF, NTN, SIP1) have been identified in affected individuals, it is now clear that RET and EDNRB are the primary genes implicated in the etiology of HSCR.
Mutations or deletions involving ZFHX1B (previously SIP1) have recently been found to cause one form of syndromic Hirschsprung disease (HSCR), associated with microcephaly, mental retardation, and distinctive facial features.