Autosomal dominant progressive external ophthalmoplegia due to the p.R357PPEO1 mutation is a late-onset ocular myopathy beginning with ptosis and progressing slowly.
Although the incidental association of OT and C10orf2 TWINKLE mutation is possible, the simultaneous onset of OT and eyelid ptosis at a much younger age than usually observed for OT raises the possibility of mitochondrial dysfunction and loss of mitochondrial DNA integrity in the pathogenesis of OT.