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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.
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.
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.
Changes in this gene are associated with 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.
These resources address the diagnosis or management of Legius syndrome and may include treatment providers.
You might also find information on the diagnosis or management of Legius syndrome in Educational resources and Patient support.
General information about the diagnosis (http://ghr.nlm.nih.gov/handbook/consult/diagnosis) and management (http://ghr.nlm.nih.gov/handbook/consult/treatment) of genetic conditions is available in the Handbook. Read more about genetic testing (http://ghr.nlm.nih.gov/handbook/testing), particularly the difference between clinical tests and research tests (http://ghr.nlm.nih.gov/handbook/testing/researchtesting).
To locate a healthcare provider, see How can I find a genetics professional in my area? (http://ghr.nlm.nih.gov/handbook/consult/findingprofessional) in the Handbook.
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.
For more information about naming genetic conditions, see the Genetics Home Reference Condition Naming Guidelines (http://ghr.nlm.nih.gov/ConditionNameGuide) and How are genetic conditions and genes named? (http://ghr.nlm.nih.gov/handbook/mutationsanddisorders/naming) in the Handbook.
Ask the Genetic and Rare Diseases Information Center (https://rarediseases.info.nih.gov/gard).
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.
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? (http://ghr.nlm.nih.gov/handbook/consult/findingprofessional) in the Handbook.