MARKED INCREASE IN MITOCHONDRIAL-DNA DELETION LEVELS IN THE CEREBRAL-CORTEX OF HUNTINGTONS-DISEASE PATIENTS

To determine if somatic mtDNA mutations might contribute to the neurodegeneration observed in con era Huntington's disease (HD), we quantitated the amount of the common mitochondrial 4977 nucleotide pair deletion (mtDNA(4977)) in cortex and putamen of HD patients and age-matched controls by the serial dilution-polymerase chain reaction method. Cortical deletion levels were analyzed in the temporal, frontal, and occipital lobes. HD temporal lobes had an Ii-fold greater mean mtDNA(4977) deletion level than age-matched controls, and HD frontal lobes had fivefold greater levels. HD occipital lobe and putamen deletion levels were comparable with control levels. These results support the hypothesis that HD is associated with elevated cortical mtDNA damage.