Traits

Traits linked to SYN1

synapsin I

The Human Phenotype Ontology links 7 traits to SYN1, by body system: features seen in people with one of the gene's rare conditions.

Abnormality of the nervous system

Trait	How often it is seen
Aggressive behavior	Very often (80–99%)
Epilepsy	Very often (80–99%)
Specific learning disability	Very often (80–99%)
Autism spectrum disorder	Not recorded
Intellectual disability, mild	Not recorded
Seizure affecting one half of brain	Not recorded

Abnormality of head or neck

Trait	How often it is seen
Big calvaria	Very often (80–99%)

How often is among people with one of the gene's conditions, the most often across them, as the Human Phenotype Ontology records it. These pages describe traits and the research behind them; they are not a diagnosis, and a doctor or genetic counsellor is the person to ask about symptoms.

Where this comes from

The Human Phenotype Ontology, release 2026-09-01: the traits linked to SYN1 and how often each is seen. Find out more at hpo.jax.org.

One test. A lifetime of answers.

From $449Free shipping · Results in 6–8 weeks

Get my Genome Test