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Shaking Up Ataxia: FGF14 and RFC1 Repeat Expansions in Affected and Unaffected Members of a Chilean Family

May 29, 2023

Monogenic Network

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The very recent discovery of intronic GAA monoallelic repeat expansions in the FGF14 (fibroblast growth factor 14) gene,1, 2 as well as the previously described biallelic repeat expansions in the RFC1 (replication factor C subunit 1) gene,3, 4 causing cerebellar ataxia, neuropathy, vestibular areflexia syndrome, have greatly enhanced the diagnostic yield in ataxia, which was previously limited to <50% even with exome sequencing.

Monogenic Network

The Monogenic Network is comprised of the (i) Data Generation Working Group and the (ii) Data Analysis Working Group, and studies patients and families with known and potential new monogenic causes of Parkinson’s disease.
Learn more about Monogenic Network

Meet the authors

Movement Disorders Neurologist

Paula Saffie Awad, MD, PhD

Clinica Santa Maria | Santiago, Chile

Associated Professor

Katja Lohmann, PhD

University of Luebeck | Germany

Head Neurogenetics Unit

Marcelo Kauffman, MD, PhD

Hospital JM Ramos Mejia | Argentina

PhD Student

Theresa Luth, PhD

University of Luebeck | Lübeck, Germany

Group leader

Joanne Trinh, PhD

University of Lübeck | Luebeck, Germany

Research Group Leader

Ana Westenberger, PhD

University of Lübeck | Lübeck, Germany

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