TCF21 and Friedreich ataxia: Overall, and based also on such data from the literature, the dysregulated expression of SLITRK5, GRIN2A, and TCF21, documented in fibroblasts of the symptomatic patient compared with her asymptomatic sister, highlight a role for these genes in the neurological (SLITRK5 and GRIN2A) and cardiac (TCF21) pathology occurring in FRDA.