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Application of whole-genome sequencing in the diagnosis of spinocerebellar ataxia type 8
https://doi.org/10.25557/2073-7998.2025.10.61-64
Abstract
Spinocerebellar ataxia type 8 (SCA8) is a rare autosomal dominant disorder caused by CTG repeat expansions in ATXN8OS/ATXN8 genes. Diagnosis of SCA8 is challenging due to clinical heterogeneity of hereditary ataxias and limitations of traditional methods. The aim of this work was to evaluate the efficacy of WGS for diagnosing SCA8 and to describe clinical cases. Patients with suspected hereditary ataxia were included. WGS was performed on the DNBSEQ-T7 platform, followed by bioinformatic analysis including STRipy for repeat expansion detection. Three families with pathogenic CTG expansions in ATXN8OS were identified. Results align with published data on variable penetrance and the influence of maternal transmission on phenotypic severity. WGS demonstrated high diagnostic efficacy for SCA8, enabling simultaneous analysis of multiple loci.
Keywords
spinocerebellar ataxia type,
SCA8,
ATXN8OS,
trinucleotide repeat expansion,
whole-genome sequencing,
WGS
Supporting agencies: The study was carried out on the state assignment of the Ministry of Science and Higher Education.
About the Authors
T. V. Vizerov
Research Centre for Medical Genetics
Russian Federation
Russian Federation
1, Moskvorechye st, Moscow 115522
K. G. Zabudskaya
Research Centre for Medical Genetics
Russian Federation
Russian Federation
1, Moskvorechye st, Moscow 115522
E. A. Melnik
Research Centre for Medical Genetics
Russian Federation
Russian Federation
1, Moskvorechye st, Moscow 115522
A. S. Kuchina
Research Centre for Medical Genetics
Russian Federation
Russian Federation
1, Moskvorechye st, Moscow 115522
O. R. Ismagilova
Research Centre for Medical Genetics
Russian Federation
Russian Federation
1, Moskvorechye st, Moscow 115522
N. S. Beskorovayny
Research Centre for Medical Genetics
Russian Federation
Russian Federation
1, Moskvorechye st, Moscow 115522
A. V. Polyakov
Research Centre for Medical Genetics
Russian Federation
Russian Federation
1, Moskvorechye st, Moscow 115522
O. P. Ryzhkova
Research Centre for Medical Genetics
Russian Federation
Russian Federation
1, Moskvorechye st, Moscow 115522
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For citations:
Vizerov T.V., Zabudskaya K.G., Melnik E.A., Kuchina A.S., Ismagilova O.R., Beskorovayny N.S., Polyakov A.V., Ryzhkova O.P. Application of whole-genome sequencing in the diagnosis of spinocerebellar ataxia type 8. Medical Genetics. 2025;24(10):61-64. (In Russ.) https://doi.org/10.25557/2073-7998.2025.10.61-64
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