Figure 2. Increased mitochondrial DNA damage compared to nucleic DNA in aged retinal pigment epithelium and choroid. DNA products from the polymerase (rTth) mediated amplification of long fragments of mitochondrial DNA (mtDNA) (13.4 kB) and nuclear DNA (nDNA) (12.5 kB) from retinal pigment epithelium (RPE) and choroid were measured. These data were normalized by the measured levels of the short fragment of mtDNA and nDNA obtained using the sample DNA template sample. As shown in Panel A, there was a significant decrease in mtDNA amplification beginning at 18 month (p=0.004, n=5), which decreased progressively at 24 month (p<0.0001, n=5) and at 32 month (p<0.0001, n=5), compared with the 4 month group. As shown in Panel B, there was no change in the nDNA amplification at 18 month (p=0.54, n=5) and 24 month (p=0.06, n=5), compared with the 4 month group. At 32 month (p=0.002, n=5), there was a significant decrease in nDNA amplification, compared with the 4 month group