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Pontocerebellar hypoplasia

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What is pontocerebellar hypoplasia?

What causes pontocerebellar hypoplasia?

What is pontocerebellar hypoplasia?

Pontocerebellar hypoplasia (PCH) is a group of conditions affecting the brain characterized by underdevelopment of the cerebellum and pons. The cerebellum normally coordinates movement and the pons (located in the brainstem) transmits signals from the cerebellum to the rest of the brain. Several forms of PCH have been described, each having some different signs and symptoms but all characterized by problems with movement, delayed psychomotor development, and intellectual disability. Although each form has a different genetic cause, they are all inherited in an autosomal recessive manner.[1][2] Many children with PCH live only into infancy or childhood, although some individuals have lived into adulthood.[1] Treatment is symptomatic and supportive.[2]
Last updated: 12/18/2012

What causes pontocerebellar hypoplasia?

The different forms of pontocerebellar hypoplasia (PCH) are generally caused by mutations in several different genes. These genes appear to play important roles in the development and survival of nerve cells. However, it is unclear how mutations in these genes disrupt the normal development of the cerebellum and pons.[1] Research thus far has found that:[1][3]
  • PCH1A can be caused by mutations in the VRK1 gene
  • PCH1B is caused my mutations in the EXOSC3 gene
  • PCH2 is caused by mutations in the TSEN54, TSEN2, TSEN34, and SEPSECS genes
  • PCH4 is caused by mutations in the TSEN54 gene
  • PCH6 is caused by mutations in the RARS2 gene
  • PCH8 is caused by mutations in the CHMP1A gene

Specific genes that cause PCH3, PCH5 and PCH7 have not yet been identified.[3]

Although experts agree that PCH has a genetic cause, other causes (such as infectious or toxic) have been reported or suspected in some cases.[4]

Last updated: 12/19/2012

  1. Pontocerebellar hypoplasia. Genetics Home Reference. December 2009; Accessed 12/18/2012.
  2. Pontocerebellar hypoplasia. NORD. March 16, 2012; Accessed 12/18/2012.
  3. PONTOCEREBELLAR HYPOPLASIA, TYPE 1A; PCH1A. OMIM. 2012; Accessed 12/19/2012.
  4. Chaves-Vischer V, Pizzolato GP, Hanquinet S, Maret A, Bottani A, Haenggeli CA. Early fatal pontocerebellar hypoplasia in premature twin sisters. Eur J Paediatr Neurol. 2000; 4(4):171-176.