The syndrome caused by pathogenic variants in the MEIS2 gene is a multisystem disorder characterized by a triad of
• cleft palate
o submucous, soft, hard and open cleft palate
• cardiac defects
o ventricle septal defect (VSD) and atrial septal defect (ASD)
• intellectual disability
o mild to severe
Other frequent features include:
• distinct facial phenotype:
o thin and arched eyebrows,
o thin upper lip vermillion,
o prominent nasal tip with short alae nasi,
o large, protruding ears with enlarged fossa triangularis and hypoplastic antihelix
• varying degrees of feeding problems
o oral aversion
o gastro-esophageal reflux
o aerophagia
o achalasia
• varying degrees of developmental delay
o mild to moderate motor delay
o severe speech delay
• autism spectrum disorder
Other clinical features described in the literature are:
• muscle hypotonia
• epilepsy
• bilateral moderate hearing loss
• behavioral abnormalities e.g., repetitive or aggressive behavior
• skeletal system abnormalities
o hypermobile joints
o scoliosis
o sandal gap
o syndactyly of toe II–III
o broad thumbs and toes
o genu valgum
• congenital lobar emphysema
• neutropenia
• dermatitis/eczema
MEIS2