[Age-dependent mitochondrial DNA 4977bp depletion in human skeletal muscle]

To explore depletion of human mitochondrial DNA 4977-bp and its relation with aging.

Total DNA (nuclear and mtDNA) was extracted from 100mg muscle tissue. UV light illumination of ethidium bromide-stained PCR products was used to study the depletion of mtDNA (wild-type or mutant).

The proportions of mtDNA depletion in human skeletal muscle could be determined. The frequency of mtDNA 4977-bp depletion in different age groups (0-9, 10-19, 20-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80-89, 90-99) was: 0%, 0%, 0.003%, 0.011%, 0.015%, 0.033%, 0.038%, 0.062%, 0.069%, and 0.091%, respectively.

Our findings suggest that the frequency of the mtDNA4977 depletion in human skeletal muscle increases with age. It might be useful for human age estimation.