Rare diseases · Sign or symptom

Abnormal cerebellum morphology

Abnormality of the cerebellum

HP:0001317

What it means

Any structural abnormality of the cerebellum.

A malformed cerebellum may be abnormally small, dysplastic, or unusually large. The vermis and both hemispheres may be equally or disproportionately affected. Primary malformations of the pons, midbrain, and supratentorial structures are also seen in a substantial subset of patients. The wide range in morphological presentations results from the diversity of causes, including chromosomal abnormalities, specific genetic syndromes, and extrinsic factors.

Rare diseases that can present with this46

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions, and Orphanet separately records 1 disease where this sign is specifically absent. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Cerebellar abnormalities · Cerebellar abnormality · Cerebellar anomaly · Cerebellar signs

Abnormal cerebellum morphology

Tracking symptoms like this for someone? Eleplan keeps symptoms, diagnoses, medications and every specialist in one plan.

Start free with Eleplan

This page uses the Human Phenotype Ontology (2026-06-23) — Human Phenotype Ontology Consortium, hpo.jax.org. Disease associations from Orphanet (INSERM), CC BY 4.0. Content is educational and is not medical advice.