Network seeks to provide DNA samples for eye disease

Key Points

Bethesda, MD-The National Ophthalmic Disease Genotyping Network (eyeGENE) is a collaborative effort involving more than 10 academic research labs to create a DNA repository coupled with prospectively obtained phenotypic and molecular diagnostic information. De-identified data and aliquots of the DNA samples will be available in the future to researchers.

The hope is that eyeGENE will facilitate discovery of new ophthalmic disease genes, help researchers identify genetic modifiers of disease, and enhance patient enrollment in clinical trials.

"The field of genetics is advancing rapidly and giving a great deal of hope and findings to patients with inherited eye diseases. The challenge, however, is translating those findings from the bench to the bedside," said Brian Brooks, MD, PhD, the founding director of eyeGENE and former chairman of its external steering committee. This effort currently is being spearheaded by the new ophthalmic genetics branch chief, Ian MacDonald, MD.

Obstacles exist

One obstacle to achieving these goals, he said, is identifying the patients. Ophthalmologists may have access to few patients with genetic eye disease in their clinical practices. A second obstacle involves the mechanics of testing, Dr. Brooks said.

"There are relatively few laboratories that can do genetic testing in such a way that the findings can be clinically reported back to the ophthalmologist," he said.

"In addition, DNA testing can be time-consuming and costly; in a busy practice it may be difficult to find and access DNA testing services," Dr. Brooks added, suggesting that it might be helpful to have one access point for the practice.

Addressing the need

The National Eye Institute (NEI) has taken steps to address this need. The institute-along with academic institutions nationwide and advisers in ophthalmology, genetics, and public policy and ethics-has created eyeGENE.

"The purpose of eyeGENE is to create a DNA repository from patients with inherited eye diseases that is coupled to a prospectively obtained database of phenotypic information," Dr. Brooks said. "The samples of these data will be anonymously available to researchers. Moreover, at the time of consent patients will have the option of being contacted again if there is a future clinical study for which they might qualify."

Another important aspect of this endeavor is that ophthalmologists will receive a written clinical report regarding DNA testing of patients. A nominal fee associated with this service covers the drawing of blood and shipping charges for the samples.

DNA testing

A distinguished panel of experts is on the steering committee, the members of which have expertise across the fields of ophthalmology and genetics. Eleven laboratories nationwide have expertise in and are participating in the DNA testing of more than 40 disease genes. These include macular diseases such as Best disease and Stargardt disease, other retinal diseases such as retinitis pigmentosa and choroideremia, certain forms of strabismus, glaucoma, and corneal dystrophies such as Reis-Buckler and granular dystrophies. Testing is not currently offered for complement factor H or the other genes associated with age-related macular degeneration. A complete listing of available tests may be obtained from the eyeGENE Web site, http://www.nei.nih.gov/resources/eyegene.asp/.

Currently, the most frequently requested tests have been for autosomal dominant X-linked forms of retinitis pigmentosa and the Mendelian macular degenerations such as Stargardt disease.

"The process begins with a conversation between the ophthalmologist and the patient, perhaps within the setting of a genetic counseling session. The patient has two questions to answer: 'Do I mind that my DNA is being used anonymously by researchers to conduct eye research?' and 'Do I want to be contacted if there is a clinical study for which I might qualify?'" Dr. Brooks said.

If the patient agrees to provide a blood sample, then the sample is drawn either through an NEI coordinating center or locally, and then it is shipped to eyeGENE. Accessing information requires online registration and the entering of certain patient phenotypic information. When the sample is received, DNA is extracted and placed in the repository for use by researchers; another sample then is sent to the appropriate DNA diagnostic laboratory.

At the laboratory, the sample is tested, and a clinical report is generated and returned to the ophthalmologist, who then can discuss the report with the patient and provide genetic counseling. A copy of the report also is maintained in the genetic database for research purposes.

Ophthalmologists interested in sending DNA samples to eyeGENE may call 301/435-3032 or e-mail eyeGENEinfo@nei.nih.gov
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