Genetic variation in the DNA of mitochondria – the 'power plants' of cells – contributes to a person’s risk of developing age-related macular degeneration (AMD), say investigators in the first study to examine the mitochondrial genome for changes associated with AMD, the leading cause of blindness in Caucasians over age 50.
“Most people don’t realize that we have two genomes,” said lead author Jeff Canter, M.D., M.P.H., an investigator in the Center for Human Genetics Research. “We have the nuclear genome – the “human genome” – that makes the cover of all the magazines, and then we also have this tiny genome in mitochondria in every cell.”
Canter teamed with Jonathan Haines, Ph.D., and Paul Sternberg, M.D., experts in AMD genetics and treatment, to examine whether a particular variation in the mitochondrial genome is associated with the disease. The genetic change occurs in about 10 percent of Caucasians, referred to as mitochondrial haplogroup T.