Rare diseases · Sign or symptom
Autism
HP:0000717
What it means
Autism is a neurodevelopmental disorder characterized by impaired social interaction and communication, and by restricted and repetitive behavior. Autism begins in childhood. It is marked by the presence of markedly abnormal or impaired development in social interaction and communication and a markedly restricted repertoire of activity and interest. Manifestations of the disorder vary greatly depending on the developmental level and chronological age of the individual (DSM-IV).
The term refers to the diagnosis of autism and is left for convenience. However, it is preferable to annotate the exact phenotypic abnormalities rather than merely the diagnostic category autism.
In everyday care
Most people with this sign do not have a rare disease — it appears in common conditions far more often. These general reference pages cover the same topic:
Rare diseases that can present with this85
Very common80–99%
4Common30–79%
24- 15q11q13microduplication syndrome
- 1p36deletion syndrome
- 2p15p16.1microdeletion syndrome
- 48,XXXY syndrome
- 49,XXXXY syndrome
- 8p inverted duplication/deletion syndrome
- Alpha-N-acetylgalactosaminidase deficiency type 1
- Bardet-Biedl syndrome
- CHARGE syndrome
- Christianson syndrome
- Intellectual disability-epilepsy-extrapyramidal syndrome
- Kleefstra syndrome due to 9q34 microdeletion
- Maternal uniparental disomy of chromosome 1 syndrome
- Placental insufficiency
- Prader-Willi syndrome due to maternal uniparental disomy of chromosome 15
- Prader-Willi syndrome due to paternal 15q11q13 deletion
- Prader-Willi syndrome due to paternal deletion of 15q11q13 type 1
- Prader-Willi syndrome due to paternal deletion of 15q11q13 type 2
- Seizures-scoliosis-macrocephaly syndrome
- Smith-Lemli-Opitz syndrome
- Tuberous sclerosis complex
- Williams syndrome
- X-linked alpha-thalassemia-intellectual disability syndrome
- X-linked intellectual disability-cerebellar hypoplasia-spondylo-epiphyseal dysplasia syndrome
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. A sign on this page is a conversation to have with a clinician, not a conclusion.
Part of the broader category
Tracking symptoms like this for someone? Eleplan keeps symptoms, diagnoses, medications and every specialist in one plan.
Start free with EleplanThis 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.