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 2 patient data entries in database for mutations R227W and P587L. Entry # | | Mutations |  | allele 1 | allele 2 |  
  | Clinical representation | Symptoms | Age group | Age of onset | Age of patient | Age of death | Reference |   |  | 12 | T251I P587L2
  | R227W4
  | PEO |  |  | 48 | n/a | n/a | Horvath et al, 2006; [view data]  |  | 263 | R227W4
  | T251I P587L2
  | PEO, bilateral ptosis, severe limita- tion of ocular motility, and a mosaic distribution of ragged-red and cytochrome c oxidase–negative fibers in the muscle biopsy. All patients had multiple deletions of muscle mtDNA. |  |  | 48 | n/a | n/a | Agostino et al, 2003; [view data]  |  
 1-5 pathogenic cluster assignment of mutations. Mutations displayed without a superscript number are outside of the assigned pathogenic clusters. See cluster definitions for details. Number of displayed patient cases: 2 Avg age of onset in displayed cases: 48.0 Std dev in onset in displayed cases: 0.0
  
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