Modeling Williams syndrome from a neurodevelopmental perspective: recent advances, model-based translational insights...

Williams syndrome (WS; OMIM #194,050) is a multisystem pediatric genetic disorder caused by a heterozygous microdeletion of a 1.5-1.8 Mb region at chromosome 7q11.23, encompassing 26 to 28 genes. Clinical hallmarks include cardiovascular anomalies, distinctive craniofacial morphology and neurodevelopmental deficits characterized by hypersociability, cognitive impairment and anxiety. Although causative therapies for WS still remain elusive, advances in gene editing and forebrain organoids have already greatly furthered our understanding of the underlying mechanisms.

This narrative review was conducted by searching for papers using PubMed/MEDLINE. Relevant publications were identified using single and/or combined keywords including: Williams syndrome, 7q11.23, microdeletion, microduplication, atypical deletion, neurodevelopment, neuroanatomy, neuroimaging. cognitive impairment, mouse models, GTF2I, GTF2IRD1, CLIP2, LIMK1, NCF1, EIF4H, STX1A/B, FZD9, HIP1, CLDN3, FKBP6, organoid, induced pluripotent stem cell (iPSC) and forebrain organoids.

Mouse models including multigene deletion strains recapitulating the WS critical region and single-gene knockout strains targeting Gtf2i, Gtf2ird1, Clip2 and Limk1 replicate key WS neurodevelopmental phenotypes, substantially contributing to mechanistic studies and therapeutic screening. In addition, forebrain organoids derived from patients or generated by gene editing have provided human-specific insights into progenitor dynamics, synaptic function, and ribosome biogenesis.

This review synthesizes recent progress in WS modeling in the context of neurodevelopmental impairments. While animal models and forebrain organoids have substantially accelerated both mechanistic understanding and translational research in WS, effective diagnostic and therapeutic approaches are still unavailable. Integration of animal models and forebrain organoids, together with the advanced technologies, will be essential for biomarker discovery and development of mechanism-based therapeutic approaches.