History of recruitment in the mitoNET registry. Between October 2009 and February 2021, 1753 patients with mitochondrial disorders (confirmed or highly suspected) were included in the mitoNET registry (0 = baseline examination). In addition, follow-up examinations (at 1 year, 2 years, etc. up to 11-year follow-up) are shown, from which it is possible to reconstruct the natural history of disorders.