APTX variant c.465del, p.(Asp156Metfs*16): Ataxia with oculomotor apraxia type 1

Ataxia with oculomotor apraxia type 1 (AOA1) is a rare autosomal recessive neurodegenerative disorder caused by mutations in the aprataxin ( APTX ) gene. It is typically characterized by childhood-onset progressive cerebellar ataxia, oculomotor apraxia, axonal sensorimotor neuropathy, and metabolic abnormalities such as hypoalbuminemia and hypercholesterolemia. We report a 33-year-old Turkish woman with a novel homozygous APTX frameshift variant (c.465del, p.Asp156Metfs*16), who presented with adolescent-onset cerebellar ataxia, oculomotor apraxia, mild dystonia, sensorimotor axonal polyneuropathy, and metabolic abnormalities, while cognition remained preserved. This case expands the genetic and phenotypic spectrum of AOA1 by illustrating a late-onset, slowly progressive phenotype associated with a previously unreported pathogenic variant.