Purpose: The authors investigated the presence of mitochondrial DNA (mtDNA) mutations in aging human retina.
Methods: A quantitative polymerase chain reaction technique for studying the common mtDNA 4977-deletion (delta mtDNA4977) in retinal pigment epithelium (RPE) and neural retinal (NR) was developed.
Results: Although no deletion was detected in the fetus, every adult RPE and NR had this common deletion. The ratio of the deleted delta mtDNA4977 to the total mtDNA increased significantly in elderly persons 60 to 110 years of age and was greater in peripheral than in central RPE.
Conclusions: These results suggest that at least one type of mutation accumulates in the mtDNA in the retina during aging, reflecting a general phenomenon of genomic instability that could influence its function.