UBR5 loss-of-function variants in autism spectrum disorder and intellectual disability: case series and review of the literature.

UBR5 encodes an E3 ubiquitin-protein ligase which targets distinct N-terminal residues of proteins for degradation. Heterozygous loss-of-function variants were reported in patients with Autism Spectrum Disorder (ASD) and developmental delay, and recently in a cohort of individuals with neurodevelopmental disorders and variable other features. Here, we report three unrelated individuals with de novo loss-of-function variants in UBR5, presenting with ASD and intellectual disability. We review the literature for other de novo predicted loss-of-function variants in probands with ASD or developmental delay (in total n = 11 variants), providing further evidence that UBR5 haploinsufficiency is associated with ASD and atypical neurodevelopmental trajectories, including developmental delay and intellectual disability.