Peripheral blood biomarkers in Friedreich's ataxia. Homo sapiens

The identification of biomarkers for Friedreich’s ataxia (FRDA), a rare and debilitating recessive Mendelian neurodegenerative disorder, is an important goal for disease follow-up and assessment of treatments. Clinical scales are not sensitive enough to detect small, short-term changes that may be indicative of treatment effectiveness. We used differential expression, correlation with expansion size, network analysis, machine learning, and enrichment analysis to identify gene expression biomarkers which differentiated FRDA patients from both heterozygous expansion carriers and controls (821 individuals in total), resulting in a disease signature for FRDA. Our 27-gene expression panel includes genes which are linked to inflammation, lipid metabolism and apoptosis, and overlaps with previous studies and a with a novel mouse model for FRDA. Future studies should seek to expand the search for FRDA biomarkers to include changes in epigenetic regulation and protein expression. Overall design: 1299 peripheral blood samples, of which 733 were used in study. 4 samples were run twice, but were not intended as technical replicates. Sample status is indicates by characteristics: sample column and can be either patient, heterozygous carrier or control