[PCR-based detection of heteroplasmic deleted mitochondrial DNA in Kearns-Sayre syndrome].

OBJECTIVE

To describe the clinical data and the results of molecular analyses of the mitochondrial DNA in a patient with Kearns-Sayre Syndrome.

METHODS

Molecular analyses of mitochondrial DNA from the patient included PCR amplification of a region where the common Kearns- Sayre deletion is located and Genotype-Phenotype correlations are discussed.

RESULTS

The affected patient showed ptosis, progressive external ophthalmoplegia, pigmentary changes in the peripheral retina and right bundle block. Molecular analysis disclosed a approximately 5 kb deletion in the mitochondrial DNA and some wild type mtDNA indicating heteroplasmy.

CONCLUSIONS

Molecular analysis of mitochondrial DNA confirmed the clinical diagnosis of Kearns-Sayre syndrome. PCR provides a rapid method to identify the common 4997 bp deletion in Kearns-Sayre syndrome. In such cases, PCR diagnosis could avoid invasive methods such as muscle biopsy or spinal tap.