Footnotes

• DT, AR and CN contributed equally.

• Contributors All the authors contributed significantly to this work. DT and AR wrote the first draft. CN, MB, AT, MP, DF, DG performed NGS studies. RB, MAD, FP, EP, RP, SG, SG performed clinical studies. SD, DT performed biochemical investigations. FMS coordinated this study.

• Funding This study was partially supported by a grant from the Italian Ministry of Health-Ricerca Corrente 5X1000 (to RB and FMS), and research projects MITO-NEXT, Mit-OMICS, and AUT-Omics (to FMS).

• Competing interests None declared.

• Provenance and peer review Not commissioned; externally peer reviewed.

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