Deletion 11q syndrome (Jacobsen 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.

Deletion 11q syndrome (Jacobsen 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. Most cases arise de novo, although inherited cases can occur. It affects males and females, although females are reported more frequently. A distinctive presentation may include the combination of widely spaced eyes, wide mouth, and ocular hypertelorism; large carp-shaped mouth; and congenital heart disease.

It can present with psychiatric features such as ADHD, autism spectrum disorder (ASD), anxiety, depression, behavioral dysregulation, and compulsive behaviors. Obsessive-compulsive disorder (OCD) has also been reported, although evidence is limited. Cognitive impairment, developmental delay, learning difficulties, and speech and language impairment are common. More severe psychiatric disorders, including bipolar disorder and psychotic disorders, have been reported rarely. These manifestations are generally recognized during childhood or development, although psychiatric and behavioral difficulties may persist into adulthood and may require ongoing assessment and support.

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

  • Microcephaly

  • Prominent metopic ridge

  • Micrognathia

  • Widely spaced eyes

  • Epicanthus

  • Ptosis

  • Depressed nasal bridge

  • Short nose

  • Wide mouth

Other characteristic features include congenital heart disease, particularly ventricular septal defects and left-sided cardiac abnormalities; Paris-Trousseau syndrome, a distinctive hematologic feature characterized by thrombocytopenia and abnormal platelet function with an increased risk of bleeding; renal and genitourinary abnormalities; and immune dysfunction with recurrent infections. Neurologic manifestations may include hypotonia, seizures/epilepsy, and structural brain abnormalities, while ophthalmologic features may include strabismus, coloboma, cataracts, and other visual abnormalities. Additional reported features include short stature, feeding difficulties, chronic constipation, skeletal abnormalities, hearing impairment, and craniosynostosis.

Early diagnosis is important to identify and monitor potentially serious cardiac, hematologic, renal, 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.