The race to translate this book of life should be over by 2002-2005 and then genetic research into disease will really begin. Certain proteins called trophic factors stimulate growth and survival of cells. They can prolong the life of dying nerve cells such as photoreceptors. Attempts are being made to use viruses to deliver genes that make these trophic factors in retinal cells near or in photoreceptors in order to slow the course of retinal degenerations in animals. The weakness of this approach is that it does not attack the root cause of the disease.
Some trophic factors can be deleterious.
Our own use of ex-vivo gene therapy to suppress neovascularization represents a similar strategy. These include radiation, photodynamic therapy, macular translocation surgery, antioxidants, low vision aids, intraocular prisms, and laser photocoagulation of drusen. These were recently reviewed in Ocular Surgery News May 15, 1998. Photodynamic surgery has promise for reducing neovascularization but the effects are too transient. Laser photocoagulation of drusen was a poor idea because it increases rather than decreases neovascularization, although this strategy appears to still be receiving large scale NEI support.