title: Gene Expression Profile in Peripheral Blood Cells of Friedreich Ataxia Patients.
abstract: Friedreich ataxia (FRDA) is the most common autosomal recessive ataxia characterized by a combination of neurological involvement, cardiomyopathy, and skeletal and glucose metabolism disturbances. FRDA is caused by mutations in FXN gene that results in reduction of mRNA and protein levels of frataxin. Previous microarray and real-time quantitative PCR (qPCR) studies showed that the downregulation of FXN is associated with a complex gene expression profile. However, these studies showed a wide variability in the subset of genes with altered expression among tissues and models. Genes differentially expressed in peripheral blood cells (PBC) could potentially help in the understanding of FRDA pathophysiology and also function as reliable disease biomarkers obtained from an easily accessible tissue, which could have implications in clinical practice. This study aimed to validate by qPCR the expression of 26 genes, revealed as differentially expressed by other studies, using peripheral blood cells (PBC) of 11 FRDA patients compared to 11 healthy controls. We found a robust downregulation of FXN, but no statistically significant differences were found between FRDA and controls for the remaining genes. Except for FXN, our study did not find a differential gene expression profile in PBC of FRDA patients and a reliable gene expression profile biomarker in a clinical relevant and noninvasive tissue remains unclear.
authors.affiliation: Division of General Neurology and Ataxia Unit, Department of Neurology and Neurosurgery, Universidade Federal de São Paulo - UNIFESP, São Paulo, SP, Brazil.|Hospital Israelita Albert Einstein, São Paulo, SP, Brazil.
authors.forename: Agessandro
authors.initials: A
authors.lastname: Abrahao
authors.affiliation: Division of General Neurology and Ataxia Unit, Department of Neurology and Neurosurgery, Universidade Federal de São Paulo - UNIFESP, São Paulo, SP, Brazil.|Hospital Israelita Albert Einstein, São Paulo, SP, Brazil.
authors.forename: Jose Luiz
authors.initials: JL
authors.lastname: Pedroso
authors.affiliation: Hospital Israelita Albert Einstein, São Paulo, SP, Brazil. patricia.aguiar@einstein.br.|Division of Movement Disorders, Department of Neurology and Neurosurgery, Universidade Federal de São Paulo - UNIFESP, Rua Pedro de Toledo 650, Vila Clementino, São Paulo, SP, 04039-002, Brazil. patricia.aguiar@einstein.br.
authors.forename: Patricia Maria
authors.initials: PM
authors.lastname: de Carvalho Aguiar
authors.affiliation: Division of General Neurology and Ataxia Unit, Department of Neurology and Neurosurgery, Universidade Federal de São Paulo - UNIFESP, São Paulo, SP, Brazil.|Hospital Israelita Albert Einstein, São Paulo, SP, Brazil.
authors.forename: Orlando Graziani Povoas
authors.initials: OG
authors.lastname: Barsottini
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood; D005260:Female; D005621:Friedreich Ataxia / Q000097:blood* / Q000235:genetics; D015870:Gene Expression; D006801:Humans; D033862:Iron-Binding Proteins / Q000097:blood; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000097:blood; D055815:Young Adult; D000096923:Frataxin
chemical_list: D015415:Biomarkers; D033862:Iron-Binding Proteins; D012333:RNA, Messenger; D000096923:Frataxin
keywords: Biomarker; Friedreich ataxia; Gene expression; Real-time quantitative PCR; qPCR