Volume 39, Issue 3 (May 1994)
Detection of the 4977 Base Pair Mitochondrial DNA Deletion in Paraffin-Embedded Heart Tissue Using the Polymerase Chain Reaction—A New Method to Probe Sudden Cardiac Death Molecular Mechanisms?
Detection of mitochondrial DNA deletions is performed in fresh or frozen material. At our institute, however, heart samples from subjects referred for autopsy are systematically processed for histologic examination (that is, paraffin-embedded). We were interested to know if mtDNA deletions can be detected in such material. Our data indicate that: 1) the most frequently observed deletion—the 4977 base pair deletion—can easily be detected in paraffin-embedded heart tissue; 2) this assay is sufficiently sensitive, since very low levels of the deletion can be found in normal heart tissue from young adults; and 3) buffered formalin appears to be the fixative of choice.
Recent literature shows that repeated episodes of ischemia result in the accumulation of mtDNA deletions in myocardial cells. Because ischemic heart disease is a major cause of sudden cardiac death, a sensitive method for the detection of mtDNA damage in myocardial cells will be an important tool to facilitate understanding of unexpected cardiac arrest mechanisms.