RT Journal Article SR Electronic T1 Cortical Overgrowth in a Preclinical Forebrain Organoid Model of CNTNAP2-Associated Autism Spectrum Disorder JF bioRxiv FD Cold Spring Harbor Laboratory SP 739391 DO 10.1101/739391 A1 Job O. de Jong A1 Ceyda Llapashtica A1 Kevin Strauss A1 Frank Provenzano A1 Yan Sun A1 Giuseppe P. Cortese A1 Karlla W. Brigatti A1 Barbara Corneo A1 Bianca Migliori A1 Steven A. Kushner A1 Christoph Kellendonk A1 Jonathan A. Javitch A1 Bin Xu A1 Sander Markx YR 2019 UL http://biorxiv.org/content/early/2019/08/19/739391.abstract AB Autism spectrum disorder (ASD) represents a major public health burden but translating promising treatment findings from preclinical non-human models of ASD to the clinic has remained challenging. The recent development of forebrain organoids generated from human induced pluripotent stem cells (hiPSCs) derived from subjects with brain disorders is a promising method to study human-specific neurobiology, and may facilitate the development of novel therapeutics.In this study, we utilized forebrain organoids generated from hiPSCs derived from patients from the Old Order Amish community with a rare syndromic form of ASD, carrying a homozygous c.3709DelG mutation in CNTNAP2 and healthy controls to investigate the effects of this mutation on cortical embryonic development.Patients carrying the c.3709DelG mutation in CNTNAP2 present with an increased head circumference and brain MRI reveals an increase in gray matter volume. Patient-derived organoids displayed an increase in total volume that was driven by an increased proliferation in neural progenitor cells, leading to an increase in the generation of cortical neuronal and non-neuronal cell types. The observed phenotypes were rescued after correction of the pathogenic mutation using CRISPR-Cas9. RNA sequencing revealed 339 genes differentially expressed between patient- and control-derived organoids of which a subset are implicated in cell proliferation and neurogenesis. Notably, these differentially expressed genes included previously identified ASD-associated genes and are enriched for genes in ASD-associated weighted gene co-expression networks.This work provides a critical step towards understanding the role of CNTNAP2 in human cortical development and has important mechanistic implications for ASD associated with brain overgrowth. This CNTNAP2 organoid model provides opportunity for further mechanistic inquiry and development of new therapeutic strategies for ASD.