Nager acrofacial dysostosis, also known as Nager syndrome, is a genetic disorder which displays several or all of the following characteristics: underdevelopment of the cheek and jaw area, down-sloping of the opening of the eyes, lack or absence of the lower eyelashes, kidney or stomach reflux, hammer toes, shortened soft palate, lack of development of the internal and external ear, possible cleft palate, underdevelopment or absence of the thumb, hearing loss (see hearing loss with craniofacial syndromes) and shortened forearms, as well as poor movement in the elbow, and may be characterized by accessory tragi.

[3] Occasionally, affected individuals develop vertebral anomalies such as scoliosis.

While Nager syndrome is thought to be most often caused by haploinsufficiency of the spliceosomal factor SF3B4,[4] in over one third of patients tested, the SF3B4 mutation is not found.

Surgical intervention is commonly necessary to increase mandibular mobility.

As the child grows and develops, further surgery is usually required on the lower jaw and is often done in tandem with orthodontic treatments.