Rare Ophthalmology News

Disease Profile

L1 syndrome

Prevalence
Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.

Unknown

Age of onset

Infancy

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ICD-10

Q04.8

Inheritance

Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease

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Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype

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X-linked
dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.

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X-linked
recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder

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Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

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Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.

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Not applicable

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Other names (AKA)

Corpus callosum hypoplasia-retardation-adducted thumbs-spasticity-hydrocephalus syndrome; CRASH syndrome; L1CAM syndrome

Summary

L1 syndrome is a mild to severe congenital disorder with hydrocephalus of varying degrees of severity, intellectual disability, spasticity of the legs, and adducted thumbs. It includes several conditions, some more severe than others: X-linked hydrocephalus with stenosis of the aqueduct of Sylvius (HSAS) the most severe of all; MASA syndrome (intellectual disability, aphasia (delayed speech), spastic paraplegia (shuffling gait), adducted thumbs); SPG1 (X-linked complicated hereditary spastic paraplegia type 1) X-linked complicated corpus callosum agenesis. It is inherited in an X-linked manner; therefore, it only affects males. It is caused by alterations (mutations) in L1CAM gene. The diagnosis is made in males who have the clinical and neurologic findings and a family history consistent with X-linked inheritance and is confirmed by a genetic test showing the L1CAM gene mutation. The treatment involves doing a surgery for the hydrocephalus.[1]

Symptoms

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Aqueductal stenosis
0002410
Depressivity
Depression
0000716
Gait disturbance
Abnormal gait
Abnormal walk
Impaired gait

[ more ]

0001288
Global developmental delay
0001263
Headache
Headaches
0002315
Hemiplegia/hemiparesis
Paralysis or weakness of one side of body
0004374
Hydrocephalus
Too much cerebrospinal fluid in the brain
0000238
Hyperreflexia
Increased reflexes
0001347
Intellectual disability
Mental deficiency
Mental retardation
Mental retardation, nonspecific
Mental-retardation

[ more ]

0001249
Language impairment
0002463
Nausea and vomiting
0002017
Spasticity
Involuntary muscle stiffness, contraction, or spasm
0001257
30%-79% of people have these symptoms
Adducted thumb
Inward turned thumb
0001181
5%-29% of people have these symptoms
Aganglionic megacolon
Enlarged colon lacking nerve cells
0002251
Seizure
0001250
Skeletal muscle atrophy
Muscle degeneration
Muscle wasting

[ more ]

0003202

Learn more

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

In-Depth Information

  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.

References

  1. Stumpel C & Vos YJ. L1 syndrome. GeneReviews. March 5, 2015; https://www.ncbi.nlm.nih.gov/books/NBK1484/. Accessed 4/24/2015.