FXN and Friedreich ataxia: Napierala et al. [82], using a new proteomic technique—reverse-phase protein array—in 44 samples of fibroblasts from FRDA patients and 18 HC, found 30 DEPs (20 upregulated and 10 downregulated), including decreased FXN and the increased expression of the enzymes aldehyde dehydrogenase 1 family member 3 (ALDH1A3) and aldehyde-oxidase 1 (AOX1), associated with oxidative stress and the regulation of retinoic acid levels.