Fig. 1.

Low CoQ₁₀level and accumulation of DMQ₁₀in the COQ7(p.Arg54Gln) patient skin fibroblasts. (A) Sanger sequencing chromatograms show a homozygous mutation at codon position 54 of exon 2 of COQ7 in the proband. His non-carrier sibling (WT) was used as a non-affected control. (B) Growth curves of skin fibroblasts derived from the proband and his non-carrier sibling (WT) (n = 6). (C) Quinone quantification in skin fibroblasts from the proband in comparison to the non-affected control. Cells were also obtained from the other healthy sibling, who is a heterozygous carrier for the variant, and were found to have comparable CoQ₁₀ levels as the non-affected control. Hom: homozygous, Het: heterozygous. Values are shown as mean ± SEM (n = 2). *p < 0.05 (two-way ANOVA followed by Tukey's multiple comparison tests). (D) HPLC chromatograms of quinone extracts from human skin fibroblasts. The patient's cells show ≈45% decrease in CoQ₁₀ level and accumulation of the biosynthetic precursor DMQ₁₀.