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.
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).
Genetics
This condition is very rare; its prevalence is unknown. Mutations in the GLI3 gene cause Pallister–Hall syndrome. The GLI3 gene provides instructions for making a protein that controls gene expression, which is a process that regulates whether genes are turned on or off in particular cells. By interacting with certain genes at specific times during development, the GLI3 protein plays a role in the normal shaping (patterning) of many organs and tissues before birth. Defects in the same gene also cause 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.
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.
Diagnosis
This section is empty. You can help by adding to it. (December 2017)
Treatment
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Notable Cases
George William Helon (Australian author and businessman) is a Pallister-Hall Syndrome (PHS) patient, mentor, counsellor and advocate.
Raul Rosas Jr. (UFC fighter) Suffers from Pallister-Hall Syndrome (PHS)
Pallister–Hall syndrome at NLM Genetics Home Reference
External links
GeneReviews/NCBI/NIH/UW entry on Pallister–Hall Syndrome
Genetics Home Reference
February 05, 2023
pallister, hall, syndrome, this, article, uses, bare, urls, which, uninformative, vulnerable, link, please, consider, converting, them, full, citations, ensure, article, remains, verifiable, maintains, consistent, citation, style, several, templates, tools, av. This article uses bare URLs which are uninformative and vulnerable to link rot Please consider converting them to full citations to ensure the article remains verifiable and maintains a consistent citation style Several templates and tools are available to assist in formatting such as Reflinks documentation reFill documentation and Citation bot documentation August 2022 Learn how and when to remove this template message This article needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed Find sources Pallister Hall syndrome news newspapers books scholar JSTOR August 2020 Learn how and when to remove this template message Pallister Hall syndrome abbreviated PHS 1 is a disorder that affects the development of many parts of the body Pallister Hall syndrome PHS Pallister Hall syndrome is inherited in an autosomal dominant pattern SpecialtyMedical genetics It is named for Judith Hall and Philip Pallister 2 3 Contents 1 Presentation 1 1 Seizures 2 Genetics 3 Diagnosis 4 Treatment 5 Notable Cases 6 References 7 External linksPresentation EditMost 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 Seizures Edit 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 Genetics EditThis condition is very rare its prevalence is unknown Mutations in the GLI3 gene cause Pallister Hall syndrome The GLI3 gene provides instructions for making a protein that controls gene expression which is a process that regulates whether genes are turned on or off in particular cells By interacting with certain genes at specific times during development the GLI3 protein plays a role in the normal shaping patterning of many organs and tissues before birth Defects in the same gene also cause 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 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 Diagnosis EditThis section is empty You can help by adding to it December 2017 Treatment EditThis section is empty You can help by adding to it December 2017 Notable Cases EditGeorge William Helon Australian author and businessman is a Pallister Hall Syndrome PHS patient mentor counsellor and advocate Raul Rosas Jr UFC fighter Suffers from Pallister Hall Syndrome PHS 4 5 References Edit Pallister Hall syndrome Genetic and Rare Diseases Information Center GARD an NCATS Program synd 506 at Who Named It 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 doi 10 1002 ajmg 1320070110 PMID 7211952 https www qt com au news man life threatening disorder needs nbn its joke 3204152 https georgehelon com wp content uploads 2018 08 George Helon Genetic Support Network jpg bare URL image file Pallister Hall syndrome at NLM Genetics Home ReferenceExternal links EditGeneReviews NCBI NIH UW entry on Pallister Hall Syndrome Genetics Home Reference Retrieved from https en wikipedia org w index php title Pallister Hall syndrome amp oldid 1126772452, wikipedia, wiki, book, books, library,
