| Patient, gender | Reference | Clinical presentation | Age of onset | Blood lactate (normal <2.5mM) | Brain abnormalities | Age at death | Variants | |
| 1, M | Kirby et al, 2004 | Lethal infantile mitochondrial disease | neonatal | 12.0 | no | 6 d | 4175pb deletion encompassing exons 3 and 4 homozygous | |
| 2a, F | Kirby et al, 2004 | Lethal infantile mitochondrial disease | neonatal | 6.4 | no | 11 d | c.186+2T>A homozygous | |
| 2b, F | Kirby et al, 2004 | Lethal infantile mitochondrial disease | neonatal | 6.7 | no | 6 d | c.186+2T>A homozygous | |
| 3a, F | Spiegel et al, 2009 | Lethal infantile mitochondrial disease | neonatal | NA | NA | 8 d | c.344G>A (p.Cys115Tyr) homozygous | |
| 3b, M | Spiegel et al, 2009 | Lethal infantile mitochondrial disease | neonatal | 6-11.2 | no | 8 d | c.344G>A (p.Cys115Tyr) homozygous | |
| 4a, F | Spiegel et al, 2009 | Lethal infantile mitochondrial disease | neonatal | elevated | NA | 6 d | c.344G>A (p.Cys115Tyr) homozygous | |
| 4b, F | Spiegel et al, 2009 | Lethal infantile mitochondrial disease | neonatal | 16.8 | NA | 8 d | c.344G>A (p.Cys115Tyr) homozygous | |
| 5, NA | Swalwell et al, 2011 | Lethal infantile mitochondrial disease | neonatal | NA | NA | NA | p.Val63Glufs*9 homozygous | |
| 6, NA | Haack et al, 2012 | Muscular hypotonia | < 6 months | elevated | no | – | c.352C>T (p.Gln118*) homozygous | |
| 7, F | Pronicka et al, 2016 | Lethal infantile mitochondrial disease | neonatal | NA | No | NA | c.313_315delAAAG (p.104Lys_106Thrfs) ; c.334_359del26ins13 (p.Glu112 fs) | |
| 8, NA | Ogawa et al, 2017 | Leigh syndrome | NA | NA | NA | NA | c.309+5G>A;
c.343T>C (p.Cys115Arg) |
|
| 9, M | Rouzier et al, 2019 | Leigh syndrome | 4 months | 4.74 | Leigh syndrome | 11 m | c.309+5G>A;
c.343T>C (p.Cys115Arg) |
|
NDUFS6