Distal Xq28 microduplication syndrome is a rare, hereditary, syndromic intellectual disability characterized by cognitive impairment, behavioral and psychiatric problems, recurrent infections, atopic diseases, and distinctive facial features in males. Females are clinically asymptomatic or mildly affected, presenting mild learning difficulties and facial dysmorphism.

Abnormally small dimension of the Maxilla. Usually creating a malocclusion or malalignment between the upper and lower teeth or resulting in a deficient amount of projection of the base of the nose and lower midface region.