FXN and Friedreich ataxia: The role of thioredoxin family proteins remains an unexplored field in FRDA, but further efforts should be made in order to clarify the specific implications of TRXs and GRXs malfunction and, in particular, their involvement in Fe-S clusters or their contribution with frataxin in Fe-S cluster biogenesis in mitochondria and how they participate to the appropriate function of IRPs and iron metabolism, all of which are crucial in the physiopathology of FRDA [144].