TP53 and neoplasm: Low levels of frataxin have also been suggested to be associated with malignancies in a number of FRDA patients and even the cause of liver tumorigenesis in mice with hepatocyte-specific disruption of FXN. 30 This observation has, however, been refuted by the analysis of large FRDA patient cohort data and by revisiting the liver tumor pathology in the conditional knockout frataxin mouse model.31 Frataxin has been proposed to be a tumor suppressor gene by Guccini et al.,32 who showed that frataxin modulates P53 expression in tumors in response to hypoxia.