Pallister W syndrome is an extremely rare congenital disorder characterized by a distinctive facies, along with mental retardation, speech problems, bone deformities, and seizures. The facial features include prominent mandible, pugilistic appearance, orofacial cleft, broad flat nasal bridge and jaw, partial adontia, high broad forehead, broad uvula, widely spaced and slanting eyes, and/or palpabral fissures. The skeletal abnormalities involve mainly the limbs and include cubitus valgus and limited elbow movement due to subluxation. Some patients may also show some signs of spasticity.

Very few cases of Pallister W syndrome have been reported worldwide. More than half of these are males. Diagnosis is based on the clinical features. The differentials to be considered include Oto-Palato-Digital syndrome, Frontometaphyseal Dysplasia, and Larsen syndrome. Treatment is symptomatic. Surgical correction of the clefting of the lip and palate, followed by speech therapy may be required. Seizures can be controlled with medications.

Pallister W syndrome is thought to be inherited as an X-linked genetic trait. This is supported by the observation that the majority of the patients are males, and that women are usually mildly affected, consistent with heterozygous manifestation.