The Cerebellum

, Volume 18, Issue 1, pp 147–151 | Cite as

Friedreich Ataxia: Diagnostic Yield and Minimal Frequency in South Brazil

  • Helena Fussiger
  • Maria Luiza Saraiva-Pereira
  • Sandra Leistner-Segal
  • Laura Bannach JardimEmail author
Short Report


Friedreich ataxia (FRDA) is an autosomal recessive disorder due to mutations in the FXN gene. FRDA is characterized by the classical triad of ataxia, absent reflexes, and Babinski sign, but atypical presentations might also occur. Our aims were to describe the proportion of FRDA diagnoses in suspected families living in Rio Grande do Sul, South Brazil, and to estimate a minimum frequency of symptomatic subjects. Subjects that were evaluated by molecular analysis for FRDA at the Hospital de Clínicas de Porto Alegre were identified in our files. Patients’ clinical manifestation and phenotypes were described and compared. The number of FRDA subjects alive in the last 5 years was determined. One hundred fifty-six index cases (families) were submitted to evaluation of GAA repeats at FXN since 1997: 27 were confirmed as FRDA patients. Therefore, the diagnostic yield was 17.3%. Proportion of classical, late onset, and retained reflexes subphenotypes were similar to those described by other studies. A minimum prevalence was estimated as 0.20:100.000 inhabitants. In conclusion, we verified that this FRDA population displayed the usual clinical characteristics, but with a lower period prevalence than those obtained in populations from Europe.


Friedreich ataxia FRDA FXN Prevalence Diagnostic yield 


Funding Information

This study was supported by the Fundo de Incentivo à Pesquisa do Hospital de Clínicas de Porto Alegre (FIPE-HCPA) (GPPG 17-0600). SLS, MLSP, and LBJ were supported by the Conselho Nacional de Pesquisa (CNPq).

Compliance with Ethical Standards

This study was approved by the local ethical committee under the registry number CAAE 79117317.2.0000.5327.

Conflict of Interest

The authors declare that they have no conflict of interest.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Programa de Pós-Graduação em Saúde da Criança e do AdolescenteUniversidade Federal do Rio Grande do SulPorto AlegreBrazil
  2. 2.Departamento de BioquímicaUniversidade Federal do Rio Grande do SulPorto AlegreBrazil
  3. 3.Laboratório de Identificação Genética, Centro de Pesquisa ExperimentalHospital de Clínicas de Porto AlegrePorto AlegreBrazil
  4. 4.Serviço de Genética MédicaHospital de Clínicas de Porto AlegrePorto AlegreBrazil
  5. 5.Departamento de Medicina InternaUniversidade Federal do Rio Grande do SulPorto AlegreBrazil

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