Skip to content

    Children's Health

    Font Size
    A
    A
    A

    L1 Syndrome

    Important
    It is possible that the main title of the report L1 Syndrome is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.

    Synonyms

    • L1 spectrum
    • L1 disease
    • MASA syndrome
    • SPG1 (X-linked complicated hereditary spastic paraplegia type 1)
    • X-linked corpus callosum agenesis
    • X-linked hydrocephalus with stenosis of the aqueduct of sylvius
    • HSAS, aqueductal stenosis, X-linked

    Disorder Subdivisions

    • None

    General Discussion

    Summary
    L1 syndrome is an inherited, X-linked disorder occurring in males that primarily affects the nervous system. The disease is mainly characterized by hydrocephalus (increased fluid in the center of the brain), spasticity of the lower limbs (muscle stiffness), adducted thumbs (clasped towards the palm), aphasia (difficulty with speaking), seizures, and agenesis of the corpus callosum (underdeveloped or absent connecting tissue between the left and right hemispheres of the brain). Affected individuals have intellectual disability in the mild to moderate range. L1 syndrome is caused by abnormalities (mutations) in the L1CAM gene, which affects about 1 in 30,000 males.

    Introduction
    The acronym CRASH (corpus callosum hypoplasia, retardation, adducted thumbs, spastic paraparesis and hydrocephalus) syndrome was originally proposed in 1995 by Dr. Erik Fransen to describe L1 syndrome but is no longer used.

    Resources

    National Hydrocephalus Foundation
    12413 Centralia Rd.
    Lakewood, CA 90715-1653
    USA
    Tel: (562)924-6666
    Fax: (562)924-6666
    Tel: (888)857-3434
    Email: nhf@earthlink.net
    Internet: http://www.nhfonline.org

    Hydrocephalus Association
    4340 East West Highway Ste 950
    Bethesda, MD 20814
    USA
    Tel: (301)202-3811
    Fax: (301)202-3813
    Tel: (888)598-3789
    Email: info@hydroassoc.org
    Internet: http://www.hydroassoc.org

    National Aphasia Association
    350 Seventh Avenue
    Suite 902
    New York, NY 10007
    USA
    Tel: (212)267-2814
    Fax: (212)267-2812
    Tel: (800)922-4622
    Email: responsecenter@aphasia.org
    Internet: http://www.aphasia.org

    NIH/National Institute of Neurological Disorders and Stroke
    P.O. Box 5801
    Bethesda, MD 20824
    Tel: (301)496-5751
    Fax: (301)402-2186
    Tel: (800)352-9424
    TDD: (301)468-5981
    Internet: http://www.ninds.nih.gov/

    NIH/National Institute on Deafness and Other Communication Disorders
    31 Center Drive, MSC 2320
    Communication Avenue
    Bethesda, MD 20892-3456
    Tel: (301)402-0900
    Fax: (301)907-8830
    Tel: (800)241-1044
    TDD: (800)241-1105
    Email: nidcdinfo@nidcd.nih.gov
    Internet: http://www.nidcd.nih.gov

    Genetic and Rare Diseases (GARD) Information Center
    PO Box 8126
    Gaithersburg, MD 20898-8126
    Tel: (301)251-4925
    Fax: (301)251-4911
    Tel: (888)205-2311
    TDD: (888)205-3223
    Internet: http://rarediseases.info.nih.gov/GARD/

    For a Complete Report:

    This is an abstract of a report from the National Organization for Rare Disorders (NORD). A copy of the complete report can be downloaded free from the NORD website for registered users. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational therapies (if available), and references from medical literature. For a full-text version of this topic, go to www.rarediseases.org and click on Rare Disease Database under "Rare Disease Information".

    The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only. NORD recommends that affected individuals seek the advice or counsel of their own personal physicians.

    It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report

    This disease entry is based upon medical information available through the date at the end of the topic. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder.

    For additional information and assistance about rare disorders, please contact the National Organization for Rare Disorders at P.O. Box 1968, Danbury, CT 06813-1968; phone (203) 744-0100; web site www.rarediseases.org or email orphan@rarediseases.org

    Last Updated: 8/2/2012
    Copyright 1997, 1998, 2005, 2012 National Organization for Rare Disorders, Inc.

    WebMD Medical Reference from the National Organization for Rare Disorders

    Last Updated: May 28, 2015
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

    Today on WebMD

    child with red rash on cheeks
    What’s that rash?
    plate of fruit and veggies
    How healthy is your child’s diet?
     
    smiling baby
    Treating diarrhea, fever and more.
    Middle school band practice
    Understanding your child’s changing body.
     

    worried kid
    fitArticle
    jennifer aniston
    Slideshow
     
    Measles virus
    Article
    sick child
    Slideshow
     

    babyapp
    New
    Child with adhd
    Slideshow
     
    rl with friends
    fitSlideshow
    Child Coughing or Sneezing into Elbow
    Article