Choroideremia is a slowly progressive inherited retinal disease caused by recessive mutations of the CHM gene that lies on the long arm of the X-chromosome. Because women have two copies of the X-chromosome and men only have one, full blown choroideremia is much more common in men than in women. Choroideremia is estimate to occur in 1/100,000 individuals in the general population. Thus, we expect about 3,400 affected individuals in the United States alone.
The discovery of the gene that causes choroideremia (by Cremers and co-workers in 1990) and the availability of a relatively inexpensive test for disease-causing alterations in this gene are both sufficiently new that most affected individuals and many eye doctors are currently unaware that such testing exists. ProjectCHM seeks to identify every person in the United States affected with choroideremia and offer them state of the art genetic testing on a nonprofit basis through the John and Marcia Carver Nonprofit Genetic Testing Laboratory at the University of Iowa. For affected families who lack health insurance, philanthropic donations will be sought to reduce the cost of the testing.
ProjectCHM has four major goals
- Provide hope.
Many individuals affected with choroideremia have been told directly or indirectly that "there is nothing that can be done” to arrest the disease or improve their vision. Project CHM seeks to reverse this message and make it clear that there is much that the individuals with choroideremia can do as a group to help combat this disease.
- Provide accurate information.
By collecting some basic clinical information from thousands of people affected with choroideremia, doctors will be able to discern the clinical severity associated with specific mutations in the CHM gene and will be able to use this information to give newly diagnosed individuals and their families more accurate information about what to expect.
- Find cures.
Trials of new treatments for choroideremia will require access to molecularly confirmed individuals affected with the disease. ProjectCHM seeks to identify and molecularly confirm as many individuals as possible affected with this disease so that clinical trials will never be slowed by a lack of suitable subjects.
- Make a genetic test for choroideremia available to all who might benefit from one.
Many insurance companies are currently unfamiliar with the value of genetic testing for choroideremia. By encouraging thousands of individuals with the disease to seek payment for their nonprofit genetic tests, ProjectCHM intends to demonstrate the value of such testing to doctors and insurance companies across the country. As a result, genetic testing will become part of the "standard of care" for choroideremia in the United States. For individuals who do not have medical insurance and who cannot afford a molecular test, Project CHM will maintain a philanthropic fund that can support the testing of these individuals.
Patients and physicians may download a form requesting financial assistance.
Information on how to order a genetic test may be found at the Project CHM Instructions Page.
Additional information regarding choroideremia may be found at the Project CHM Resource Page.