Publication
Title
Clinico-genetic, imaging and molecular delineation of COQ8A-ataxia : a multicenter study of 59 patients
Author
Abstract
Objective: To foster trial-readiness of coenzyme Q8A (COQ8A)-ataxia, we map the clinicogenetic, molecular, and neuroimaging spectrum of COQ8A-ataxia in a large worldwide cohort, and provide first progression data, including treatment response to coenzyme Q10 (CoQ10). Methods: Cross-modal analysis of a multicenter cohort of 59 COQ8A patients, including genotype-phenotype correlations, 3D-protein modeling, in vitro mutation analyses, magnetic resonance imaging (MRI) markers, disease progression, and CoQ10 response data. Results: Fifty-nine patients (39 novel) with 44 pathogenic COQ8A variants (18 novel) were identified. Missense variants demonstrated a pleiotropic range of detrimental effects upon protein modeling and in vitro analysis of purified variants. COQ8A-ataxia presented as variable multisystemic, early-onset cerebellar ataxia, with complicating features ranging from epilepsy (32%) and cognitive impairment (49%) to exercise intolerance (25%) and hyperkinetic movement disorders (41%), including dystonia and myoclonus as presenting symptoms. Multisystemic involvement was more prevalent in missense than biallelic loss-of-function variants (82-93% vs 53%; p = 0.029). Cerebellar atrophy was universal on MRI (100%), with cerebral atrophy or dentate and pontine T2 hyperintensities observed in 28%. Cross-sectional (n = 34) and longitudinal (n = 7) assessments consistently indicated mild-to-moderate progression of ataxia (SARA: 0.45/year). CoQ10 treatment led to improvement by clinical report in 14 of 30 patients, and by quantitative longitudinal assessments in 8 of 11 patients (SARA: -0.81/year). Explorative sample size calculations indicate that >= 48 patients per arm may suffice to demonstrate efficacy for interventions that reduce progression by 50%. Interpretation: This study provides a deeper understanding of the disease, and paves the way toward large-scale natural history studies and treatment trials in COQ8A-ataxia.
Language
English
Source (journal)
Annals of neurology. - Boston, Mass.
Publication
Hoboken : Wiley , 2020
ISSN
0364-5134
DOI
10.1002/ANA.25751
Volume/pages
p. 1-13
ISI
000539105500001
Pubmed ID
32337771
Full text (Publisher's DOI)
Full text (open access)
UAntwerpen
Faculty/Department
Research group
Project info
Solving the unsolved Rare Diseases (Solve-Rd).
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identifier
Creation 17.07.2020
Last edited 02.10.2024
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