A. Muir

De novo variants in the poly(rC)-binding protein gene PCBP1 cause a neurodevelopmental disorder.

Monoallelic loss-of-function variants in ZNF536 are associated with a neurodevelopmental disorder with prominent behavioral features.

ZNF536 encodes a C2H2 zinc-finger transcription factor that functions as a transcriptional repressor. While common noncoding variants at the ZNF536 locus have been reported to be associated with schizophrenia in a genome-wide association study (GWAS), the contribution of rare, protein-altering variants to human disease has not been systematically investigated. Through an international collaboration, we assembled a cohort of 21 affected individuals carrying 18 unique, rare, heterozygous, protein-altering ZNF536 variants. Most variants (15/18) were predicted loss-of-function (LoF) alleles, with the remainder being missense variants. Among families with available inheritance data (17/20), most variants arose de novo (12/17), while others were inherited from mosaic or mildly affected parents (5/17). Clinically, affected individuals presented with developmental delay along with high rates of autism spectrum disorder, intellectual disability, hyperactivity, aggressive behavior, anxiety, and hyperphagia; epilepsy and sleep disturbances were also frequently observed. To assess functional consequences of a proband-associated ZNF536 variant, we generated a Zfp536p.Gln169Ter knock-in mouse model. Homozygous mutants were non-viable, while heterozygotes survived but displayed autism-like behaviors, increased anxiety, and impaired recognition memory. Embryonic brain analysis revealed reduced cortical size, cortical thickness, and decreased deep-layer neuronal density. These features are consistent with phenotypes of a publicly available mouse knockout model and support our clinical cohort findings that rare monoallelic LoF variants in ZNF536 underlie a genetic neurodevelopmental disorder characterized by developmental delay, autism, and behavioral dysregulation. The pathogenicity of missense variants in disease remains to be determined. These results support a role for ZNF536 as a dosage-sensitive regulator of cortical development.

The clinical and molecular spectrum of AGO2-associated Lessel-Kreienkamp neurodevelopmental syndrome

AGO2 is established as a pivotal regulator of neurodevelopment whose structural integrity is essential for precise miRNA-mediated gene regulation and isomiR generation, and occurrence of gonadal mosaicism is reported and revealed.

De novo missense variants in TRIM28 identified in individuals with neurodevelopmental delay show features of transposable element activation

This study describes two patients with neurodevelopmental delay who carry de novo TRIM28 missense variants and demonstrates that these variants result in the loss of the histone mark H3K9me3 over TEs, establishing a link between TRIM28 variants and neurodevelopmental delay.