 However, Hirschsprung's disease is not present in all infants with Mowat–Wilson syndrome and therefore it is not a required diagnostic criterion.Distinctive physical features include microcephaly, narrow chin, cupped ears with uplifted lobes with central depression, deep and widely set eyes, open mouth, wide nasal bridge and a shortened philtrum.The disorder is expressed in an autosomal dominant fashion and may result from a de novo loss of function mutation or total deletion of the ZEB2 gene located on chromosome 2q22.