Legius syndrome (LS) is an autosomal dominant condition characterized by cafe au lait spots. It was first described in 2007 and is often mistaken for [1 ] Neurofibromatosis type I (NF-1). It is caused by mutations in the SPRED1 gene. [2 ] [3 ] It is also known as [4 ] Neurofibromatosis Type 1-like syndrome (NFLS). The syndrome is named after Eric Legius, Professor at the KU Leuven. It is a RASopathy.
Symptoms [ edit ]
Nearly all patients show multiple
Café au lait spots. Other symptoms may include:
Features common in neurofibromatosis -
Lisch nodules, bone abnormalities, neurofibromas, optic pathway gliomas and malignant peripheral nerve sheath tumors - are absent in this condition.
Diagnosis [ edit ]
Genetic testing is necessary to identify the syndrome. The test checks for loss of function
mutations in the SPRED1 gene.
Confusion with Neurofibromatosis Type I [ edit ]
The symptoms of Legius syndrome and NF-1 are very similar. This is the reason why the two are easily confused. A genetic test is often the only way to make sure a person has LS and not NF-1. The similarity of symptoms stem from the fact that the different genes affected in the two syndromes code for proteins that carry out a similar task in the same reaction pathway.
An important difference is the absence of tumor growths (
Lisch nodules and Neurofibromas which are common in NF-1) in LS. [5 ]
Because of this difference, Legius syndrome is often seen as the less severe of the two syndromes.
Disease Database [ edit ]
SPRED1 gene variant database
See also [ edit ]
References [ edit ]
^ "Legius syndrome", Genetics Home Reference, National Institutes of Health
^ "SPRED1", Genetics Home Reference, National Institutes of Health
^ "Legius Syndrome Often Mistaken for Neurofibromatosis Type 1", by Allison Gandley, November 18, 2009, Medscape
^ "Legius Syndrome (SPRED1) Sequencing & (NF1) Sequencing Exon 22 (Exon 17)", May 2010, ARUP Laboratories
^ a b , Pagon RA, Bird TD, Dolan CR, et al.