The Real Life of Ataxia Patients Without a Vertical Family History: a Twenty-year Experience in South Brazil.

Authors

Carlos Alberto Moura Aschoff, Thiago Oliveira Silva, Ali Hasan, Elaine Migliorini, Karina Carvalho Donis, Rare Genomes Project Consortium, David Pellerin, Maria Luiza Saraiva-Pereira, Sandra Leistner, Fabiano Poswar, Roberto Giugliani, Cristina Brinckmann Oliveira Netto, Patrícia Ashton-Prolla, Jonas Alex Morales Saute, Laura Bannach Jardim

Published in

Cerebellum (London, England). Volume 25. Issue 5. Aug 19, 2026. Epub Aug 19, 2026.

Abstract

Studies of hereditary ataxias (HA) without vertical family history are necessary for designing diagnostic protocols. We described the 20 years' experience of a Brazilian reference service with these cases through a retrospective cohort study of subjects evaluated from 2002 to 2020 in a university hospital. Tests for Friedreich ataxia, alpha-fetoprotein, common dominant ataxias, and brain imaging were the first steps, whereas ataxia Sanger panel, exome or genome sequencings (NGS) were the last ones. The outcomes were: diagnosis; no diagnosis after NGS; or incomplete diagnostic investigation. Diagnoses and diagnostic yields were also presented. 174 subjects started investigation and 120 came to the second visit: 45/120 received a diagnosis, 12/120 finished their investigation without a diagnosis, and 63/120 were incompletely investigated. Higher-than-expected proportions of white subjects and of people coming from small communities were found. Most common diagnoses were Friedreich ataxia, ataxia-telangiectasia, Coenzyme Q10 deficiency, Niemann-Pick type C, ataxia with oculoapraxia type 2, and spinocerebellar ataxia type 2. Thirty-two subjects were investigated by NGS; among them, 5/7 ataxia Sanger panels, 9/17 exome and 1/7 genome sequencings got a molecular diagnosis, with diagnostic yields of 71.4%, 52.9% and 14%, respectively. The high proportion of patients lost to follow-up, cases with incomplete investigation and white individuals suggest problems in the access to healthcare. Exome and Sanger panels were the most efficient methods for reaching a diagnosis. The fact they are not easily available in the public health system is an important barrier to overcome, hopefully soon.

PMID:
42616279
Bibliographic data and abstract were imported from PubMed on 20 Aug 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.