Empowering prevention of Glaucoma*
deCODE´s research has identified two sequence variants in a gene called LOXL1 that significantly increase the risk of developing exfoliation glaucoma. The effect is thought to be through what is called exfoliation syndrome which is characterized by accumulation of abnormal microfibrillar deposits that line the aqueous bathed surfaces of the anterior segment of the eye.
According to deCODE’s research the effect of the identified genetic risk variants seem to be in addition to and independent of other known risk factors such as intraocular pressure and age. This means that even though at this point in time there is no known remedy or actions that can be specifically taken to counteract the genetic risk associated with the LOXL1 variants, the overall risk for vision loss as a consequence of undetected exfoliation glaucoma may be decreased through frequent eye exams and physician recommended interventions.
Independent of the family history for glaucoma knowing ones genetic make-up in regard to deCODE’s genetic exfoliation glaucoma risk markers is relevant since they may be part of the familial risk or an addition to it.
The deCODE Glaucoma™ test therefore offers a new factor and added weight to the analysis of an individual’s risk for glaucoma which may help the individual and his/her physician to decide on future monitoring, prevention and/or specific treatments.
About Exfoliation Glaucoma
Glaucoma is a heterogeneous group of disorders that share a distinct pattern of optic nerve damage. There are two basic forms of glaucoma, open- and closed angle glaucoma. In most populations, open-angle glaucoma, characterized by painless loss of vision, constitutes the majority of glaucoma cases. Open-angle glaucoma is defined as a progressive loss of neuroretinal rim tissue within the optic disk and consequent excavation of the optic disk with corresponding loss of visual field and is divided into primary open-angle glaucoma and secondary glaucoma. Primary open angle glaucoma is without an identifiable cause of aqueous outflow resistance, whereas in secondary glaucoma including exfoliation glaucoma, the outflow resistance is of a known cause. The prevalence of exfoliation glaucoma increases with age, and although the disease is found worldwide, a number of studies have pointed to a geographical clustering of the syndrome.
Exfoliation syndrome is the most common identifiable cause of secondary glaucoma in most populations. According to recent studies the 15-year risk of exfoliation syndrome conversion to exfoliation glaucoma is about 60%. Exfoliation glaucoma is characterized by rapid progression, high resistance to medical therapy, and a worse prognosis than in primary open angle glaucoma. Family history is an important risk factor for both primary open angle glaucoma and exfoliation syndrome which, together with ethnic differences in prevalence of primary open angle glaucoma, points to a role of genetic factors in the risk of suffering from these conditions.
The discovery of glaucoma genes provides a method for early detection of glaucoma. Genetic testing is capable of identifying those at highest risk for developing glaucoma. Such patients would include family members of patients with known glaucoma gene defects and members of families with a strong history of inherited glaucoma. About 10-30% of all primary open angle glaucoma patients have the LOXL1 glaucoma gene defect, but about 25 % of the general population (white Caucasians) are positive for the test Glaucoma gene testing of those who are at high risk for developing glaucoma may be of value followed by regular monitoring of the eye pressure by a physician.
If you have additional questions regarding the deCODE study or the deCODE Glaucoma™ test, please contact deCODE at diagnostics@decode.com, or by phone at 1-877-222-6510 and a deCODE representative will respond promptly to your questions.