Expanding the TBL1XR1 Disease Spectrum: Generalized Dystonia Associated with a New Genetic Variant.

BACKGROUND: A growing number of identified genes increasingly reveal genetic overlaps between neurodevelopmental disorders and combined dystonia syndromes. CASE REPORT: We report a 61-year-old man with a neurodevelopmental disorder, mild ataxic signs and generalized dystonia who had been misdiagnosed with cerebral palsy for 40 years. Whole-exome sequencing identified a novel heterozygous pathogenic frameshift variant in TBL1XR1. DISCUSSION: TBL1XR1 variants are classically associated with Pierpont syndrome and autism spectrum disorder. Although movement disorders have been reported, this case suggests generalized dystonia as a possible additional manifestation. It highlights the value of retrospective genetic phenotyping and next-generation sequencing in adults with long-standing neurodevelopmental diagnoses.