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
Neurofibromatosis type I (NF-1). It is caused by mutations in the
SPRED1 gene. It is also known as
Neurofibromatosis Type 1-like syndrome (NFLS). The syndrome is named after Eric Legius, Professor at the
KU Leuven. It is a
RASopathy.