1 Department of Medical Genetics, Reference Centre for Mitochondrial Diseases, CHU Nice, Nice, France sylvie.bannwarth@univ-cotedazur.fr veronique.paquis@univ-cotedazur.fr.
2 Université Côte d'Azur (UniCA), Inserm U1081, CNRS UMR 7284, IRCAN, Nice, France.