Biallelic RFC1 pentanucleotide repeat expansions in Greek patients with late‐onset ataxia. Issue 1 (29th March 2021)

• Record Type: Journal Article
• Authors: Kontogeorgiou, Zoi; Kartanou, Chrisoula; Tsirligkani, Chrysanthi; Anagnostou, Evangelos; Rentzos, Michail; Stefanis, Leonidas; Karadima, Georgia; Koutsis, Georgios
• Is Part Of: Clinical genetics. Volume 100:Issue 1(2021)
• Page Start: 90
• Page End: 94
• Publication Date: 2021-03-29
• Subjects: CANVAS -- cerebellar ataxia -- Greek population -- pentanucleotide expansion -- RFC1 -- sensory neuropathy; Medical genetics -- Periodicals; 616.0420
• DOI: 10.1111/cge.13960
• Languages: English
• ISSNs: 0009-9163

Abstract

Abstract: Cerebellar ataxia, neuropathy and vestibular areflexia syndrome (CANVAS) has been recently linked to biallelic expansions of a pentanucleotide repeat in the replication factor C subunit 1 ( RFC1 ) gene. Herein, we sought to investigate the presence of pathological RFC1 expansions in selected Greek patients with late‐onset ataxia and delineate the phenotypic spectrum of genetically confirmed CANVAS in the Greek population. We screened genetically a total of 77 selected index patients, 67 originating from a cerebellar ataxia cohort and 10 from a hereditary neuropathy cohort. We identified five index cases (6.5%) with biallelic pathological RFC1 expansions, two in the cerebellar ataxia cohort (3%) and three in the neuropathy cohort (30%). Overall, four out of five of cases with full‐blown CANVAS and one case with sensory ataxic neuropathy had biallelic pathological expansions. The phenotypic spectrum of positive cases (including two affected siblings) was consistent with previous reports and implied that the sensory neuropathy may be the earliest feature in genetically confirmed CANVAS. Screening for biallelic RFC1 expansions is recommended in all cases with late‐onset ataxia of unknown cause, particularly when a sensory neuropathy is present. Abstract :