Elucidating ADNP Syndrome Gene Dysregulation through a Novel Approach in iPSC-Derived GABAergic Neuron Development [ADNP_scRNA-seq]

GABAergic interneurons are essential for maintaining neural circuit function, and their dysfunction is linked to a range of neurodevelopmental and neurodegenerative disorders. Traditional approaches for differentiating human pluripotent stem cells (PSCs) into neuronal cells are often hindered by challenges such as incomplete neural differentiation, prolonged culture times, and variability across PSC lines. To overcome these limitations, we developed an innovative strategy by combining the overexpression of transcription factors Ascl1 and Dlx2 with dual-SMAD and WNT inhibition, effectively driving the differentiation of PSCs into diverse, region-specific GABAergic neuron subtypes. Through single-cell sequencing, we thoroughly characterized the heterogeneity of these induced neurons (iNs) and uncovered the regulatory mechanisms underlying their fate specification. Our findings demonstrate the successful generation of multiple disease-relevant GABAergic neuron types. Furthermore, we investigated the impact of the ADNP syndrome-associated p.Tyr719* variant on GABAergic neuron differentiation, revealing that this mutation significantly alters neuronal subtype composition and synaptic transmission. This study advances our understanding of the diversity of PSC-derived GABAergic neurons and underscores their potential as models for exploring neurological disorders.