May 2007

Genetic Variants and the Development of Age-Related Macular Degeneration

In recent years, specific varieties of two independent genes have been linked to an increased risk for developing age-related macular degeneration (AMD). More recently, scientists at Tufts-New England Medical Center predicted which individuals were likely to develop more serious forms of AMD. In a study published in the April 25, 2007 issue of the Journal of the American Medical Association, researchers discovered that subjects with both of these genetic variants were seven times more likely than those without the variants to develop advanced AMD. The study followed 1,466 patients with early or intermediate AMD over a six-year period. The researchers note, however, that only 4% of the United States population inherits both genes and further research is required to better understand the roles and functions of such genes in the development of advanced AMD. (Source: Journal of the American Medical Association )

Drug That Treats AMD May Increase Stroke Risk

Use of Genentech's new eye drug, Lucentis, might increase the risk of stroke, according to a letter the company has begun sending to doctors. In the letter, Genentech stated that interim data from a clinical trial indicated that 1.2 % of patients treated with the recommended higher dosage of Lucentis had suffered strokes — compared with 0.3 % of patients treated with a lower dosage of the drug. The difference is considered statistically significant. Approved to treat AMD, Lucentis is the first drug shown in clinical trials to improve eyesight for a significant number of patients, as opposed to merely slowing the rate of vision loss. You can read more about the Lucentis study in The New York Times.

Sensory Arts & Science Receives U.S. Patent 7,166,079 for MacScope, an Early Detection Method for AMD

Sensory Arts & Science recently announced that the United States Patent and Trademark Office issued a patent for its MacScope method and technology. The MacScope is a computer-based screening method for identifying the presence of irregularities in the macula. The patent, entitled "Methods and Apparatus for Observing and Recording Irregularities of the Macula and Nearby Retinal Field," was issued on January 23, 2007. The MacScope is currently being tested in a multi-center clinical trial in the Philadelphia area in order to determine its effectiveness in detecting early stage AMD. Further study will determine if additional eye pathologies can be detected with the MacScope, such as diabetic retinopathy. You can read more about this new AMD technology here.

Update on Stem Cell Transplants for AMD

AMD targets a protective lining inside the eye, called the retinal pigment epithelium (RPE), which provides nutrients to the photoreceptor cells and is vital for their survival. A transplant of fresh RPE tissue could rescue dying photoreceptors, but this approach is neither practical nor feasible for the millions of Americans who show signs of early AMD; thus, scientists at the biotechnology firm Advanced Cell Technology have attempted to generate a more abundant and reliable source of RPE cells. In 2004, they devised a way to transform embryonic stem cells into transplantable RPE tissue and, in a follow-up experiment, injected the transformed cells/new tissue into the eyes of rats with a genetic defect in their RPE cells. As reported in the September 2006 issue of Cloning and Stem Cells, the rats receiving the treatment were able to track stripes on a rotating cylinder twice as well as those that did not. You can read more about this embryonic stem cell research in Scientific American.

Educational Video About AMD and Low Vision Increases Knowledge but Not Behavior

An educational and motivational video, designed to increase subjective emotional well being and the use of adaptive devices by patients with AMD, did increase knowledge but did not change behavior or emotions, said Schepens Eye Research Institute scientists in a study reported in the March issue of Optometry & Vision Science. "While our video succeeded in increasing patients' knowledge of macular degeneration and the availability of adaptive devices and techniques, it did not change their emotional response to their disease or motivate them to make changes that could improve their quality of life," said Dr. Eli Peli, senior scientist at Schepens and senior author of the study. You can read more about the video and study at Newswise.

"Vision Loss," Not "Blindness"

Until last fall, according to Dan Roberts, director of Macular Degeneration Support and author of The First Year: Age-Related Macular Degeneration, a major portion of media releases about AMD included statements such as "AMD is the leading cause of blindness among senior citizens." After researching the issue and initiating a publicity campaign, Roberts now reports that a majority of press releases and media broadcasts are now using the term "vision loss." Roberts, who has AMD, spent five months tracking public articles and news broadcasts about AMD on the Internet. In November 2006, he discovered that 58% used the word "blind" to describe AMD. As of March 2007, he reported that usage of "blind" had dropped to 42%, with the trend continuing downward. His poll is described in the online presentation How Blind Is Blind?. You can read more about his research here.