Cortical overgrowth in a preclinical forebrain organoid model of CNTNAP2-associated autism spectrum disorder

We utilized forebrain organoids generated from induced pluripotent stem cells of patients with a syndromic form of Autism Spectrum Disorder (ASD) with a homozygous protein-truncating mutation in CNTNAP2, to study its effects on embryonic cortical development. Patients with this mutation present with clinical characteristics of brain overgrowth. Patient-derived forebrain organoids displayed an increase in volume and total cell number that is driven by increased neural progenitor proliferation. Single-cell RNA sequencing revealed PFC-excitatory neurons to be the key cell types expressing CNTNAP2. Gene ontology analysis of differentially expressed genes (DEgenes) corroborates aberrant cellular proliferation. Moreover, the DEgenes are enriched for ASD-associated genes. The cell-type-specific signature genes of the CNTNAP2-expressing neurons are associated with clinical phenotypes previously described in patients. The organoid overgrowth phenotypes were largely rescued after correction of the mutation using CRISPR-Cas9. This CNTNAP2-organoid model provides opportunity for further mechanistic inquiry and development of new therapeutic strategies for ASD. Mutations in CNTNAP2 have been associated with a syndromic form of Autism Spectrum Disorder. Here the authors show that forebrain organoids generated from induced pluripotent stem cells of patients with a syndromic form of ASD with a homozygous truncating mutation in CNTNAP2 displayed an increase in volume and total cell number, which is driven by abnormal cellular proliferation and neurogenesis.

Automated summary

Mutations in CNTNAP2 have been linked to a specific form of Autism Spectrum Disorder. Using forebrain organoids derived from induced pluripotent stem cells of patients with this mutation, the study found that the increased volume and cell number were driven by abnormal cellular proliferation and neurogenesis, offering insights into potential therapeutic strategies for ASD.