Recent Advances in the Genetics of Ataxias: An Update on Novel Autosomal Dominant Repeat Expansions.

Purpose Of Review: Autosomal dominant cerebellar ataxias, also known as spinocerebellar ataxias (SCAs), are genetically and clinically diverse neurodegenerative disorders characterized by progressive cerebellar dysfunction. Despite advances in sequencing technologies, a large proportion of patients with SCA still lack a definitive genetic diagnosis. The advent of advanced bioinformatic tools and emerging genomics technologies, such as long-read sequencing, offers an unparalleled opportunity to close the diagnostic gap for hereditary ataxias.

The GAA repeat expansion is a major cause of ataxia in the Cypriot population.

Dominantly inherited intronic GAA repeat expansions in the fibroblast growth factor 14 gene have recently been shown to cause spinocerebellar ataxia 27B. Currently, the pathogenic threshold of (GAA) repeat units is considered highly penetrant, while (GAA) is likely pathogenic with reduced penetrance. This study investigated the frequency of the GAA repeat expansion and the phenotypic profile in a Cypriot cohort with unresolved late-onset cerebellar ataxia.

Measurement Properties of the Dysphagiameter for the Assessment of Dysphagia in Oculopharyngeal Muscular Dystrophy.

Oculopharyngeal muscular dystrophy (OPMD) is a rare late-onset muscle disease with progressive dysphagia as a major symptom. The Dysphagiameter is a newly developed patient-reported outcome measure (PROM) to assess the severity of dysphagia and its impact in patients with OPMD. This article reports on item reduction and a first assessment of the Dysphagiameter's psychometrics properties, in a French and English-speaking population of individuals with OPMD.

The First Case of Autosomal Recessive Cerebellar Ataxia with Prominent Paroxysmal Non-kinesigenic Dyskinesia Caused by a Truncating FGF14 Variant in a Turkish Patient.

Background: ATX-FGF/SCA27A has been exclusively associated with heterozygous variants in the FGF14 gene, presenting with postural tremor, slowly progressive cerebellar ataxia, and psychiatric and behavioral disturbances.

Objectives: This study describes the first case of ATX-FGF/SCA27A linked to a biallelic frameshift variant in the FGF14 gene.

Methods: Whole-exome sequencing (WES) was conducted using the Illumina NovaSeq 6000 platform, and the identified variant was confirmed using Sanger sequencing.