World Library  
Flag as Inappropriate
Email this Article

Pallister–Hall syndrome

 

Pallister–Hall syndrome

Pallister–Hall syndrome
Classification and external resources
ICD-10 D33.0
OMIM 146510
DiseasesDB 32013
MeSH D054975

Pallister–Hall syndrome is a disorder that affects the development of many parts of the body.

It is named for Judith Hall and Philip Pallister.[1][2]

Contents

  • Presentation 1
  • Genetics 2
  • Seizures 3
  • External links 4
  • References 5

Presentation

Most people with this condition have extra fingers and/or toes (polydactyly), and the skin between some fingers or toes may be fused (cutaneous syndactyly). An abnormal growth in the brain called a hypothalamic hamartoma is characteristic of this disorder. In many cases, these growths do not cause any medical problems; however, some hypothalamic hamartomas lead to seizures or hormone abnormalities that can be life-threatening in infancy. Other features of Pallister–Hall syndrome include a malformation of the airway called a bifid epiglottis, laryngeal cleft, an obstruction of the anal opening (imperforate anus), and kidney abnormalities. Although the signs and symptoms of this disorder vary from mild to severe, only a small percentage of affected people have serious complications.

Genetics

This condition is very rare; its prevalence is unknown. Mutations in the GLI3 gene cause Pallister–Hall syndrome. The Greig cephalopolysyndactyly syndrome.

Mutations that cause Pallister–Hall syndrome typically lead to the production of an abnormally short version of the GLI3 protein. Unlike the normal GLI3 protein, which can turn target genes on or off, the short protein can only turn off (repress) target genes. Researchers are working to determine how this change in the protein's function affects early development. It remains uncertain how GLI3 mutations can cause polydactyly, hypothalamic hamartoma, and the other features of Pallister–Hall syndrome.

Pallister–Hall syndrome is inherited in an autosomal dominant pattern.

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. In some cases, an affected person inherits a mutation in the GLI3 gene from one affected parent. Other cases result from new mutations in the gene and occur in people with no history of the disorder in their family.

Seizures

As noted above, the hypothalamic hamartoma can cause seizures. The most common types of seizures that occur are known as gelastic epilepsy. The term gelastic originates from the Greek word "gelos which means "laughter". Seizures may begin at any age but usually before three or four years of age. The seizures usually start with laughter and the laughter is often described as being "hollow" or "empty" and not very pleasant. The laughter occurs suddenly, comes on for no obvious reason and is usually completely out of place. The most common areas of the brain which give rise to gelastic seizures are the hypothalamus (a small but extremely important structure deep in the centre of the brain), the temporal lobes and the frontal lobes. If the child has gelastic seizures and precocious puberty, then it is likely that the child will be found to have a hypothalamic hamartoma (a hamartoma in the hypothalamus part of the brain).

External links

  • GeneReviews/NCBI/NIH/UW entry on Pallister–Hall Syndrome
  • [1]
  • [2]

References

  1. ^ synd/506 at Who Named It?
  2. ^ Hall JG, Pallister PD, Clarren SK, et al. (1980). "Congenital hypothalamic hamartoblastoma, hypopituitarism, imperforate anus and postaxial polydactyly--a new syndrome? Part I: clinical, causal, and pathogenetic considerations". Am. J. Med. Genet. 7 (1): 47–74.  
  • Pallister–Hall syndrome at NLM Genetics Home Reference
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 


Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.