A protocol for detection of mitochondrial DNA deletions: characterization of a novel deletion

Clin Biochem. 1998 Nov;31(8):627-32. doi: 10.1016/s0009-9120(98)00074-5.


Objectives: To develop a protocol capable of identifying deletions in mitochondrial DNA and use it to identify the breakpoints of a mtDNA deletion in a patient with chronic progressive external ophthalmoplegia (CPEO).

Design and methods: Deletions in mtDNA were identified by a combination of long range PCR and Southern blotting. The precise breakpoints were determined by automated DNA sequencing.

Results: A series of DNA samples from patients with suspected mitochondrial disease was subjected to a protocol, which combines long range PCR and Southern blotting. We found a unique deletion in a patient with CPEO and we identified the precise location of this deletion through DNA sequencing.

Conclusions: Long range PCR has the advantages of speed, minimal samples requirements, and sensitivity. Southern blotting is better able to evaluate heteroplasmy and detect duplications. We suggest a protocol that enables us to identify precisely the breakpoints in a unique mutation of mtDNA in a patient with CPEO.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Blepharoptosis / genetics
  • Blotting, Southern / methods*
  • DNA, Mitochondrial / analysis*
  • Humans
  • Kearns-Sayre Syndrome / genetics
  • Male
  • Mitochondrial Encephalomyopathies / genetics
  • Ophthalmoplegia / genetics*
  • Ophthalmoplegia, Chronic Progressive External / genetics
  • Polymerase Chain Reaction / methods*
  • Sensitivity and Specificity
  • Sequence Deletion*


  • DNA, Mitochondrial