Williams syndrome (Williams-Beuren 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.

Williams syndrome (Williams-Beuren syndrome) is a rare genetic disorder. It is caused by a recurrent deletion of genetic material from the long arm of chromosome 7. The condition is usually de novo, although it can be inherited in an autosomal dominant manner, so absence of a relevant family history does not exclude the diagnosis. A distinctive presentation may include the combination of thick vermilion of the lips, a hoarse voice, supravalvular aortic stenosis, and a highly sociable and empathetic behavioral phenotype.

It can present with psychiatric features such as anxiety, specific phobias, ADHD, emotional dysregulation, perseverative behaviors, and sleep disturbance. Marked social disinhibition, overfriendliness, and excessive empathy are particularly characteristic and may coexist with difficulties recognizing social boundaries. Autism spectrum disorder (ASD) has also been reported, although it appears to be substantially less common than anxiety and ADHD. Cognitive impairment is usually mild, with a distinctive cognitive profile characterized by relative strengths in language and verbal short-term memory alongside marked visuospatial impairment. Developmental delay and fine motor difficulties are common.

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

  • Microcephaly

  • Coarse face

  • Short palpebral fissure

  • Epicanthus

  • Fullness of eyelids

  • Depressed nasal bridge

  • Short nose

  • Long philtrum

  • Thick vermilion

  • Small nails

Other characteristic features include hypotonia, growth deficiency, and connective tissue abnormalities, including joint hypermobility and later joint contractures, as well as a characteristically hoarse voice. Cardiovascular manifestations are particularly important and may include supravalvular aortic stenosis, peripheral pulmonary artery stenosis, hypertension, and stenosis of other arteries. Endocrine manifestations may include hypercalcemia, hypercalciuria, hypothyroidism, early puberty, and diabetes mellitus. Additional reported features include hearing impairment and hypersensitivity to sound, strabismus and refractive errors, feeding difficulties, constipation and other gastrointestinal abnormalities, urinary tract abnormalities, dental abnormalities, and scoliosis.

Early diagnosis is important to identify and monitor potentially serious cardiovascular, endocrine, renal, auditory, ophthalmologic, gastrointestinal, and developmental 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.