Fig. 3.

MPV17 mutation causes multiple mtDNA deletions. (a) Long range PCR of muscle DNA shows significant evidence of multiple mtDNA deletions. Lane 1, DNA size marker; lane 2, patient; lane 3, age-matched control. (b) Quantitative, single fibre real-time-PCR showing many COX-deficient fibres containing high levels of a clonally-expanded mtDNA deletion involving the MTND4 gene. (c) Sequence chromatogram highlighting the c.298C>T (p.Pro98Leu) MPV17 mutation identified in our patient. (d) Amino acid alignments of the mpv17 protein from different species confirms a strict conservation of p.Pro98 throughout species from human to yeast.