Ablepharon-Macrostomia Syndrome

Ablepharon macrostomia syndrome (AMS) is an extremely rare, autosomal dominant genetic disorder characterized by abnormal phenotypic appearances that primarily affect the head and face as well as the skull, skin, fingers and genitals. AMS generally results in abnormal ectoderm-derived structures. The most prominent abnormality is the underdevelopment (microblepharon) or absence of eyelids – signifying the ablepharon aspect of the disease – and a wide, fish-like mouth – macrostomia. Infants presenting with AMS may also have malformations of the abdominal wall and nipples. Children with AMS might also experience issues with learning development, language difficulties and intellectual disabilities.
AMS is caused by mutations in the TWIST2 gene, among others. It is closely related to Barber–Say syndrome in terms of phenotypic abnormalities.