2.4 Determination of mitochondrial DNA copy number
The mitochondrial DNA copy number (mtDNA CN) was calculated through
real-time quantitative polymerase chain reaction (qPCR) using the
PRISM® 7900HT Fast Real-Time PCR System (Applied
Biosystems, Foster City, CA, USA). The primer sequences (Cosmogenetech,
Daejeon, Korea) used are described in supplementary methods. The mtDNA
CN was calculated with adjustments to the standard curve of a
calibrator, which contained exactly one copy of mtDNA and one copy of
nuclear DNA.