Börjeson-Forssman-Lehmann 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.

Börjeson-Forssman-Lehmann syndrome is an X-linked genetic condition. It can occur as an inherited or de novo genetic condition, so absence of a relevant family history does not exclude the diagnosis. It occurs predominantly in males, while females with pathogenic variants can have a variable phenotype ranging from minimal manifestations to features overlapping those seen in males. A distinctive presentation may include large ears, hypogonadism, and intellectual disability.

It can present with psychiatric features such as ADHD, externalising or challenging behaviour, impulsivity, and thrill-seeking behaviour. Social interest and sociability may be relatively well preserved. Autistic traits and stereotyped or repetitive behaviours have also been described. Hypersexual behaviour has been reported but is not a consistent feature. Behavioural manifestations can persist into adulthood, although their severity varies considerably between individuals.

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

  • Microcephaly

  • Prominent supraorbital ridges

  • Coarse face

  • Ptosis

Other characteristic features include hypotonia, seizures, and speech and language difficulties. Other manifestations may include truncal obesity, gynaecomastia in males, short stature, digital and dental abnormalities, retinal or other ocular abnormalities, and structural brain abnormalities.

Early diagnosis is important to identify developmental, behavioural, neurological, endocrine, and other medical complications; provide appropriate developmental, educational, and behavioural support; and allow appropriate management of seizures, obesity, hypogonadism, and other potentially significant complications.

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.