Primer-shift PCR in detection of an age-associated 4977-bp deletion of mitochondrial DNA in human muscle tissues

Accumulation of mitochondrial DNA (mtDNA) mutations has been proposed to be an important contributor to aging and degenerative disease in various organ systems. In this study, we applied the primer-shift polymerase chain reaction (PCR) technique to detect the 4977-bp deleted mtDNA, the most common and abundant deletion of mtDNA, in muscles of human subjects of different ages. The deletion was found in 2 out of 15 patients (13.3%) of the 30-39 age group, 2 out of 12 patients (16.7%) of the 40-49 age group, 3 out of 16 patients (18.7%) of the 50-59 age group, 5 out of 19 patients (26.3%) of the 60-69 age group, and 4 out of 12 patients (33.3%) of the 70-79 age group. No subjects younger than 30 years of age displayed the deleted mtDNA. The frequency of occurrence of the deleted mtDNA increased with age. Our findings suggest that the mtDNA 4977-bp deletion in the human muscle is associated with the aging process.