Benefits for Albertans
But vision research isn't only about potential. The work done by Dr. Walter and others has led to some immediate benefits for Albertans. Through a program funded by the Alberta government, Capital Health offers molecular diagnostic testing to patients who may have inherited eye disorders. Currently the service is geared mainly to glaucoma. Patients with strong family histories of glaucoma can be tested to see whether they carry any of the mutations known to predispose people to the condition. If they do carry one of these mutations, frequent eye examinations are recommended, so that, if glaucoma was diagnosed in the future, they would be able to start treatment at an early stage. If they don't have the mutations, they are at no more risk than the rest of the general population and do not require frequent testing.
"To our knowledge this service, which is funded by the province, is unique in the world," says Heritage Clinical Investigator Dr. Ordan Lehmann, an ophthalmologist and genetics researcher at the University of Alberta. "We're translating basic research to improve the clinical service we offer patients. As we identify more genes that cause disease, they can be built into the testing process."
The close link between basic science and patient care is one of the things that attracted Dr. Lehmann to Alberta from the United Kingdom in 2004. "Every so often a patient comes along who sparks an important research question," he says. "As a clinician-scientist, I can take those questions and investigate them in the lab." For example, Dr. Lehmann was intrigued by a young patient referred to him with developmental eye disease. By studying her DNA, he and his lab colleagues were able to narrow the problem down to a particular gene that, when it mutates, causes a number of eye diseases, including childhood blindness. The work was done in partnership with Dr. Andrew Waskiewicz, a professor of biological sciences who directs the University of Alberta zebrafish facility. The zebrafish is an important animal model for vision research.
The project highlights Dr. Lehmann's interest in chromosomal abnormalities—that is, extra copies of chromosomes, or missing chromosomes. For decades, these have been known to cause such relatively rare diseases as Down syndrome. "Besides that, it was assumed that chromosomes were relatively boring repositories of information that didn't do very much," explains Dr. Lehmann. In fact, nothing could be further from the truth. In the past few years, technology has improved to the point where it is possible to detect very small duplications and deletions in chromosomes. Such rearrangements are now considered to be as important a cause of human disease as mutations (DNA sequence changes).
"My personal view is that real breakthroughs in vision science, as well as in other areas of medicine, are going to come from research at the molecular level," says Dr. Lehmann. "After all, some three-quarters of human diseases have a heritable basis. As a physician, I'm aware that knowledge about chromosomes and genes is not enough. The key challenge is to translate what you find into clinical practice. We're developing a team at the University of Alberta and Capital Health that is breaking down the barriers between the research lab and the clinic."