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 neurod egeneration observed in con era Huntington's disease (HD), we quantita ted the amount of the common mitochondrial 4977 nucleotide pair deleti on (mtDNA(4977)) in cortex and putamen of HD patients and age-matched controls by the serial dilution-polymerase chain reaction method. Cort ical deletion levels were analyzed in the temporal, frontal, and occip ital lobes. HD temporal lobes had an Ii-fold greater mean mtDNA(4977) deletion level than age-matched controls, and HD frontal lobes had fiv efold greater levels. HD occipital lobe and putamen deletion levels we re comparable with control levels. These results support the hypothesi s that HD is associated with elevated cortical mtDNA damage.