National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Cerebellar hypoplasia

Cerebellar hypoplasia is a neurological condition in which the cerebellum is not completely developed or is smaller than it should be. It may occur with a variety of congenital syndromes, metabolic disorders and neurodegenerative disorders; therefore signs and symptoms may depend upon the associated condition an affected individual has.[1] The most common findings are developmental and speech delay, poor muscle tone (hypotonia), ataxia and abnormal ocular (eye) movements. Cerebellar hypoplasia may range from mild or partial underdevelopment to complete absence (agenesis). It may affect only the cerebellum, or also affect other central nervous system structures. The inheritance pattern may differ depending on the underlying cause of the condition.[2] Treatment is generally symptomatic and supportive and depends upon the underlying disorder and the severity of symptoms.[1]
Last updated: 10/26/2015
The main clinical symptoms are poor muscle coordination (ataxia), decreased muscle tone (hypotonia), developmental or language delay and eye problems.[3][4]
Last updated: 10/26/2015

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

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Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Abnormality of eye movement
Abnormal eye movement
Abnormal eye movements
Eye movement abnormalities
Eye movement issue
[ more ] 		0000496
Ataxia 0001251
Muscular hypotonia
Low or weak muscle tone
0001252
30%-79% of people have these symptoms
Abnormality of movement
Movement disorder
Unusual movement
[ more ] 		0100022
Behavioral abnormality
Behavioral changes
Behavioral disorders
Behavioral disturbances
Behavioral problems
Behavioral/psychiatric abnormalities
Behavioural/Psychiatric abnormality
Psychiatric disorders
Psychiatric disturbances
[ more ] 		0000708
Hypertonia 0001276
Macrocephaly
Increased size of skull
Large head
Large head circumference
[ more ] 		0000256
Microcephaly
Abnormally small skull
Decreased circumference of cranium
Decreased size of skull
Reduced head circumference
Small head circumference
[ more ] 		0000252
Neurological speech impairment
Speech disorder
Speech impairment
Speech impediment
[ more ] 		0002167
Seizure 0001250
Percent of people who have these symptoms is not available through HPO
Autosomal recessive inheritance 0000007
Cerebellar hypoplasia
Small cerebellum
Underdeveloped cerebellum
[ more ] 		0001321
Generalized hypotonia
Decreased muscle tone
Low muscle tone
[ more ] 		0001290
Nystagmus
Involuntary, rapid, rhythmic eye movements
0000639
Tremor 0001337
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Last updated: 7/1/2020
It is believed that the cerebellar hypoplasia is due to a defect in the neuronal proliferation and neuronal migration during development of the embryonic nervous system. Cerebellar hypoplasia may result after an atrophy (destruction) of the cerebral cortex on the opposite side.[3][4] There are some documented cases in the literature in which cerebellar hypoplasia has been associated with autosomal recessive and X-linked patterns of inheritance.[5][6] There are also several genetic syndromes in which cerebellar hypoplasia is a finding. In other cases, it may be secondary and due to some environmental factors like viral infections, drugs or radiation, but none of these factors has been confirmed.[7]
Last updated: 10/26/2015

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

In-Depth Information

  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Cerebellar hypoplasia. Click on the link to view a sample search on this topic.

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  1. Cerebellar Hypoplasia. NINDS. September 29, 2011; https://www.ninds.nih.gov/Disorders/All-Disorders/Cerebellar-Hypoplasia-Information-Page.
  2. Isolated cerebellar hypoplasia/agenesis. Orphanet. February 2005; http://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=EN&Expert=1398.
  3. Buyse ML . Birth defects Encyclopedia. Dover, MA: Center for Birth Defects Information Services; 1990;
  4. Wassmer E, Davis P, Whitehouse WP & Green SH. Clinical spectrum associated with cerebellar hypoplasia. Pediatric Neurology. May 2003; 28(5):347-351. http://www.pedneur.com/article/S0887-8994(03)00016-X/abstract.
  5. Scotto CE, Paredes MA & Manassero GM. Un caso de hipoplasia cerebelar humana asociada a consanguinidad multiple. 2006; http://www.usmp.edu.pe/medicina/horizonte/2006_II/Art6_Vol6_N2.pdf.
  6. Fenichel GM. Clinical Pediatric Neurology. Malformaciones cerebelosas.Hipoplasia Congénita de los hemisferios.p.231 y p.241. España. 2006: Elsevier; 2006;
  7. Rodriguez B & cols.. Hipoplasia cerebelosa congénita: informe de un caso y revisión de la literatura. Patología. 1994;