Expanding the Phenotypic Spectrum of -Related Intellectual Disability: Description of Two Portuguese Patients and Review of the Literature.

Introduction: Pathogenic variants in have been associated with a neurodevelopmental disorder mainly characterized by intellectual disability, severe language impairment, and motor developmental delay. Since its first description in 2016, only 15 patients have been described in the literature.

Methods: Here, we report 2 additional unrelated Portuguese children presenting intellectual disability and motor delay in whom de novo nonsense pathogenic variants in have been identified by next-generation sequencing analysis.