A research team led by John Guy, M.D., professor of ophthalmology at Bascom Palmer Eye Institute at the University of Miami Miller School of Medicine, has pioneered a novel technological treatment for Leber Hereditary Optic Neuropathy (LHON), an inherited genetic defect that causes rapid, permanent, and bilateral loss of central vision in people of all ages, but primarily males ages 20-40. Guy and his team recently advanced their research significantly by demonstrating that the vector, adeno-associated virus or AAV (a small virus that infects humans but is not known to cause disease), coupled with the ND4 gene, was made human grade expressed in the ex vivo human eye and was proven safe in experimental models that are closest to the human eye, suggesting possible progression to a clinical trial.

These latest findings will be shared in the January 23 online edition of the Journal of the American Medical Association Ophthalmology under the title "Safety and Effects of the Vector for the Leber's Hereditary Optic Neuropathy Gene Therapy Clinical Trial." Funding for a clinical trial, which would allow injection of therapeutic genes into patients who have visual loss from mitochondrial disease, is currently being sought from governmental and other appropriate sources.

Guy's preliminary research was funded in 2007 by National Institutes of Health (NIH) and National Eye Institute (NEI) grants totaling $6.1 million. It has been found that mutations in the mitochondria (part of the cell that produces energy) cause LHON. Currently, there is no treatment for this or any other disease caused by mutated mitochondrial DNA. However, Guy and his team previously modified a virus and used it to introduce healthy genes into the mitochondria to correct the genetic defect.

"In research conducted in 2012, we proved that it is both safe and effective to replace mutated genes with healthy ones and that doing so prevents deterioration of the retinal cells that form the optic nerve," said Guy. "This research demonstrated that when efficiently introduced into mitochondria, normal DNA can correct a biochemical defect in cellular energy production and restore visual function."

For more go to: http://med.miami.edu/news/bascom-palmer-eye-institute-announces-lhon-breakthrough

University of Miami Miller School of Medicine
Marla Bercuson, 305-326-6190
mbercuson@med.miami.edu