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Reviewed February 2011
What is Legius syndrome?
Legius syndrome is a condition characterized by changes in skin coloring (pigmentation). Almost all affected individuals have multiple café-au-lait spots, which are flat patches on the skin that are darker than the surrounding area. Another pigmentation change, freckles in the armpits and groin, may occur in some affected individuals.
Other signs and symptoms of Legius syndrome may include an abnormally large head (macrocephaly) and unusual facial characteristics. Although most people with Legius syndrome have normal intelligence, some affected individuals have been diagnosed with learning disabilities, attention deficit disorder (ADD), or attention deficit hyperactivity disorder (ADHD).
Many of the signs and symptoms of Legius syndrome also occur in a similar disorder called neurofibromatosis type 1. It can be difficult to tell the two disorders apart in early childhood. However, the features of the two disorders differ later in life.
Read more about neurofibromatosis type 1.
How common is Legius syndrome?
The prevalence of Legius syndrome is unknown. Many individuals with this disorder are likely misdiagnosed because the signs and symptoms of Legius syndrome are similar to those of neurofibromatosis type 1.
What genes are related to Legius syndrome?
Mutations in the SPRED1 gene cause Legius syndrome. The SPRED1 gene provides instructions for making the Spred-1 protein. This protein controls (regulates) an important cell signaling pathway that is involved in the growth and division of cells (proliferation), the process by which cells mature to carry out specific functions (differentiation), cell movement, and the self-destruction of cells (apoptosis). Mutations in the SPRED1 gene lead to a nonfunctional protein that can no longer regulate the pathway, resulting in overactive signaling. It is unclear how mutations in the SPRED1 gene cause the signs and symptoms of Legius syndrome.
Read more about the SPRED1 gene.
How do people inherit Legius syndrome?
This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder.
Where can I find information about diagnosis or management of Legius syndrome?
These resources address the diagnosis or management of Legius syndrome and may include treatment providers.
General information about the diagnosis and management of genetic conditions is available in the Handbook. Read more about genetic testing, particularly the difference between clinical tests and research tests.
To locate a healthcare provider, see How can I find a genetics professional in my area? in the Handbook.
Where can I find additional information about Legius syndrome?
You may find the following resources about Legius syndrome helpful. These materials are written for the general public.
You may also be interested in these resources, which are designed for healthcare professionals and researchers.
What other names do people use for Legius syndrome?
What if I still have specific questions about Legius syndrome?
Where can I find general information about genetic conditions?
The Handbook provides basic information about genetics in clear language.
These links provide additional genetics resources that may be useful.
What glossary definitions help with understanding Legius syndrome?
ADHD ; apoptosis ; attention deficit disorder ; attention deficit hyperactivity disorder ; autosomal ; autosomal dominant ; cell ; differentiation ; disabilities ; gene ; groin ; hyperactivity ; inherited ; macrocephaly ; pigmentation ; prevalence ; proliferation ; protein ; syndrome
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
See also Understanding Medical Terminology.
References (6 links)
The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? in the Handbook.