Diseases & Conditions


A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Lissencephaly


Synonyms of Lissencephaly
  • agyria
  • lissencephaly, type I

Disorder Subdivisions

  • isolated lissencephaly sequence (ILS)
  • lissencephaly 1 (LIS1)
  • Miller-Dieker syndrome
  • Norman-Roberts syndrome
  • subcortical band heterotopia
  • x-linked lissencephaly


General Discussion
Classical lissencephaly, also known as lissencephaly type I, is a brain malformation that may occur as an isolated abnormality (isolated lissencephaly sequence [ILS]) or in association with certain underlying syndromes (e.g., Miller-Dieker syndrome, Norman-Roberts syndrome). The condition is characterized by absence (agyria) or incomplete development (pachygyria) of the ridges or convolutions (gyri) of the outer region of the brain (cerebral cortex), causing the brain's surface to appear unusually smooth.

In infants with classical lissencephaly, the head circumference may be smaller than would otherwise be expected (microcephaly). Additional abnormalities may include sudden episodes of uncontrolled electrical activity in the brain (seizures), severe or profound mental retardation, feeding difficulties, growth retardation, and impaired motor abilities. If an underlying syndrome is present, there may be additional symptoms and physical findings.

Researchers indicate that there may be various possible causes of isolated lissencephaly, including viral infections or insufficient blood flow to the brain during fetal development or certain genetic factors. Changes (mutations) of at least two different genes have been implicated in isolated lissencephaly: a gene located on chromosome 17 (known as LIS1) and a gene located on the X-chromosome (known as XLIS or Doublecortin). There is a third gene known as TUBA1A that has been identified as the 3rd genetic cause for this disorder.

Organizations related to Lissencephaly
  • Lissencephaly Contact Group
    209-211 City Road
    London Intl EC1V 1JN
    Phone #: 020- 76-08 8700
    800 #: 080-8 8-08 3555
    e-mail: info@lissencephaly.org.uk
    Home page: http://www.lissencephaly.org.uk
  • MUMS (Mothers United for Moral Support, Inc) National Parent-to-Parent Network
    150 Custer Court
    Green Bay WI 54301-1243
    Phone #: 920-336-5333
    800 #: 877-336-5333
    e-mail: mums@netnet.net
    Home page: http://www.netnet.net/mums/
  • Madisons Foundation
    PO Box 241956
    Los Angeles CA 90024
    Phone #: 310-264-0826
    800 #: N/A
    e-mail: getinfo@madisonsfoundation.org
    Home page: http://www.madisonsfoundation.org
  • National Institute of Neurological Disorders and Stroke (NINDS)
    31 Center Drive
    Bethesda MD 20892-2540
    Phone #: 301-496-5751
    800 #: 800-352-9424
    e-mail: braininfo@ninds.nih.gov
    Home page: http://www.ninds.nih.gov/



For a Complete Report

This is an abstract of a report from the National Organization for Rare Disorders, Inc. ? (NORD). A copy of the complete report can be obtained for a small fee by visiting the NORD website. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational treatments (if available), and references from medical literature. For a full-text version of this topic, see http://www.rarediseases.org/search/rdblist.html