Duplication 15q syndrome

Page most recently updated 7 September 2026

This page focuses on the reported psychiatric associations, which may be the initial presenting manifestation, and on other clinical features that may assist the psychiatrist or primary care physician in identifying the underlying diagnosis, considered through the lenses of the diagnostic lenses framework.

Duplication 15q syndrome is a rare genetic disorder. It can occur as an inherited or de novo genetic condition, so absence of a relevant family history does not exclude the diagnosis. The duplication is typically of maternal origin, and inherited cases are transmitted through the mother. It affects males and females, with no clear sex predilection. A distinctive presentation may include the combination of a broad nasal bridge, camptodactyly (permanent flexion of one or more fingers), and cardiac defects.

It can present with psychiatric features such as ADHD, autism spectrum disorder (ASD), anxiety, emotional lability, behavioral dysregulation, and hyperactivity. Mood disorders and psychosis have also been reported, although psychosis appears to be uncommon. Cognitive impairment, developmental delay, and speech and language impairment are common. These manifestations generally emerge during childhood or development, although behavioral and psychiatric difficulties may persist into adulthood and require ongoing assessment and support.

From a morphologic lens perspective, other features include (but are not limited to):

  • Micrognathia

  • Short neck

  • Short palpebral fissure

  • Downslanted palpebral fissures

  • Ptosis

  • Broad nasal bridge

  • Long philtrum

  • Long fingers

Other characteristic features include epilepsy, particularly infantile spasms, hypotonia and motor delay; feeding difficulties and gastrointestinal problems, including constipation; and sleep disturbances, including parasomnias and sleep-disordered breathing. Neurologic manifestations may include ataxia, tremor, and other abnormal movements. Additional reported features include cardiac defects, strabismus, scoliosis, joint hypermobility, and recurrent respiratory or ear infections.

Early diagnosis is important to identify and monitor potentially serious neurologic and ophthalmologic complications, recognize neuropsychiatric needs early, and institute tailored multidisciplinary surveillance and treatment.

Selected references and further reading — Morphologic lens

Jones KL, Jones MC, del Campo M. Smith's recognizable patterns of human malformation. 8th ed. Philadelphia: Elsevier; 2021.

Reardon W. The bedside dysmorphologist: a guide to identifying and assessing congenital malformations. 2nd ed. Oxford: Oxford University Press; 2016.

Allanson JE, Biesecker LG, Carey JC, Hennekam RCM. Elements of morphology: introduction. Am J Med Genet A. 2009;149A(1):2-5. doi:10.1002/ajmg.a.32601.

Hennekam RCM, Biesecker LG, Allanson JE, Hall JG, Opitz JM, Temple IK, Carey JC; Elements of Morphology Consortium. Elements of morphology: general terms for congenital anomalies. Am J Med Genet A. 2013;161A(11):2726-2733. doi:10.1002/ajmg.a.36249.