Neural Tube Defects: Genetics

Michelle R O'Byrne, The University of Texas Medical School at Houston, Houston, Texas, USA
Kit Sing Au, The University of Texas Medical School at Houston, Houston, Texas, USA
Hope Northrup, The University of Texas Medical School at Houston, Houston, Texas, USA

Published online: November 2010

DOI: 10.1002/9780470015902.a0006233.pub2

Neural tube defects (NTDs) are malformations of the brain and the spinal cord, resulting from lack of closure of the developing neural tube during embryological development. NTDs are complex birth disorders with a worldwide prevalence from 0.5 to 2.0 per 1000 births. The two most common types of NTD are anencephaly and spina bifida, which involve failure of neural tube closure in the cranial and in the back regions respectively. NTDs are hypothesised to be a result of genetic abnormalities and environmental factors; yet, the aetiology remains undetermined. Research studies over the past decade have indicated that maternal folate deficiency is an extremely important risk factor for an NTD birth, with maternal folate supplementation decreasing risk. However, the role that folate plays in NTD risk is not well defined.

Key Concepts:

  • Neural tube defects (NTDs) are congenital malformations of the brain and spinal cord.
  • The prevalence rates of NTDs vary worldwide.
  • NTDs are complex birth defects composed of both genetic and environmental components.
  • The underlying mechanism remains undetermined.
  • NTDs are classified by whether they are open or closed and by the location of the lesion.
  • Folic acid supplementation ameliorates NTD risk.
  • The majority of NTDs are sporadic and nonsyndromic.
  • To date, association studies in relatively small patient cohorts have been used in an attempt to find causative genes.
  • Future additional approaches will include Genome-Wide Association Study (GWAS) and high-throughput sequencing.

Keywords: genetics; neural tube defects; complex disorder; folic acid; candidate genes

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    book Wyszynski DF (2006) Neural Tube Defects, From Origin to Treatment. New York, NY: Oxford University Press.
 Web Links
    ePath International Clearing House for Birth Defects Research: http://www.icbdsr.org/
    ePath Morbidity and Mortality Weekly Report: http://www.cdc.gov/mmwr/

Related Sub-Topics:

Neurobiology of Disease | Nervous System Development | Development of Vertebrate Nervous System | Developmental Disorders | Molecular Genetics of Common and Complex Disease
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Article Title: Neural Tube Defects: Genetics
 
How to Cite close
O'Byrne, Michelle R, Au, Kit Sing, and Northrup, Hope(Nov 2010) Neural Tube Defects: Genetics. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0006233.pub2]