Summary
A medRxiv preprint reports rare biallelic BECN1 variants in two unrelated families and connects the gene to AMPA-receptor regulation. Mouse and zebrafish experiments support the proposed biological mechanism.
Researchers report rare, harmful variants affecting both copies of BECN1 in two unrelated families with neurodevelopmental disorders. In a medRxiv preprint posted October 15, 2026, they also describe mouse and zebrafish experiments that connect BECN1 to neuronal development, social behaviour and the regulation of AMPA receptors.
The findings combine human genetic observations with experiments in model organisms. The authors propose that BECN1 has a role in brain development through a pathway involving the ubiquitin-proteasome system, in addition to its known association with autophagy.
Human genetics and model evidence
“Biallelic” means that variants are present in both copies of a gene. The researchers identify rare deleterious biallelic BECN1 variants in two unrelated families and report that disrupting Becn1 in mice and zebrafish produces neuronal and social-development defects.
The animal experiments provide a way to investigate how BECN1 could affect development. They do not, by themselves, establish how the variants influence the course of disease in people. The human findings described in the abstract are limited to two families, and the report is a preprint rather than a peer-reviewed journal publication.
A proposed link to AMPA receptors
The authors describe BECN1 as an adaptor: a protein that helps bring other molecules together. In their proposed pathway, BECN1 recruits Arc to UBE3A, an E3 ubiquitin ligase. UBE3A then promotes Arc’s polyubiquitination and degradation. The researchers say this process helps maintain the stability of postsynaptic AMPA receptors and AMPA-receptor-mediated excitatory signalling.
AMPA receptors are proteins on nerve cells that respond to glutamate, a major excitatory signalling chemical in the brain. Their activity helps transmit signals between neurons. The proposed pathway therefore connects BECN1 to synaptic communication through protein turnover: the cell’s process for tagging and breaking down proteins.
The study offers a candidate molecular explanation linking BECN1 variants with neurodevelopmental effects, supported by genetic findings in families and experiments in two vertebrate models. Its results are preliminary, and the abstract does not provide enough clinical detail to describe the range or frequency of features among affected people.