Mowat-Wilson syndrome is a genetic disorder arising from mutations/deletions in the ZEB2 gene and is manifested by a characteristic facial appearance, growth disorders, and central nervous system anomalies such as mental retardation, seizures, or agenesis of the corpus callosum. Mowat-Wilson syndrome is also associated with other disorders including congenital heart diseases, Hirschsprung disease, and genitourinary abnormalities.
Mowat-Wilson syndrome is a genetic disease affecting females twice as often as males . This syndromic illness presents with a variety of clinical manifestations which include a distinctive facies, developmental anomalies, central nervous system, cardiac, gastrointestinal, and genitourinary disorders.
A typical facial appearance is one of the most predominant features seen in Mowat-Wilson syndrome patients, present in up to 98% of affected individuals. Palatal anomalies are seen commonly with cleft palate, bifid uvula, and a high arched palate being the common findings . Some patients present with velopharyngeal insufficiency, micrognathia, glossoptosis, or laryngeal/tracheal abnormalities.
Amongst the most common central nervous system manifestations of Mowat-Wilson syndrome are focal/absence seizures (seen in 70-75% of patients) and agenesis of the corpus callosum (seen in approximately 50% of patients) . Other less frequent findings include hippocampal dysgenesis, cerebral atrophy, and external hydrocephalus with ventriculomegaly.
Intellectual disability is universally present in patients with Mowat-Wilson syndrome with a large number of individuals having impaired verbal language skills. Repetitive behaviors and antisocial personalities are commonly seen.
Structural congenital heart disorders affecting the pulmonary arteries and/or the valves are seen in a high percentage of cases. Pulmonary artery slings, atrial or ventricular septal defects, coarctation of the aorta, patent ductus arteriosus, and tetralogy of Fallot may be some of the manifestations .
The diagnosis of Mowat-Wilson syndrome is suspected in patients presenting with the typical clinical features associated with the disease. An atypical presentation is seen only in approximately 2% of individuals and hence, all investigations are geared towards detecting the common anomalies seen in this syndrome (namely the congenital heart diseases, Hirschsprung disease, agenesis of the corpus callosum etc.)
Patterns on electroencephalograms (EEG) are usually unrelated to the structural brain disorders seen in this syndrome with only mild slowing of background activity evident on initial evaluation. Repeat testing may show the characteristic seizure patterns.
All patients suspected of having Mowat-Wilson syndrome must undergo genetic testing of the ZEB2 gene. Sequence analysis of the gene may help detect mutations whilst fluorescence in situ hybridization (FISH) may identify submicroscopic deletions  . Polymerase chain reaction (PCR) may enable detection of other genetic abnormalities responsible for this syndrome.