Pseudoexfoliation glaucoma syndrome ... (pseudoexfoliation glaucoma syndrome) - Gen LOXL1
Syndrome pseudoexfoliation glaucoma is a disorder characterized by abnormal accumulation of fibrillar deposits in the anterior segment of the eye that can affect nerve fibers of the retina and consequently affect vision. Besides being a cause of glaucoma and glaucomatous optic neuropathy, syndrome has also been associated with weak crystalline, cataract formation, and systemic vascular complications due to deposition of material exfoliation extraocular tissues. The prevalence increases with age and can affect between 20% and 30% in people over 60 years.
Signs and symptoms of the disease include abnormalities in the lens, ciliary body, iris, trabecular meshwork, and the corneal endothelium, which could lead to significant clinical problems, including complications of cataract surgery and development of glaucoma. Pseudoexfoliation syndrome has been associated with signs of ocular ischemia as indicate the presence of iris neovascularization, alteration in the flow and occlusion of the central retinal vein, cardiovascular and cerebrovascular disorders, and asymptomatic myocardial dysfunction. For this last anomaly, affected people have a higher prevalence of ischemic heart disease.
This process is due to mutations in the gene LOXL1, located on the long (q) arm of chromosome 15 (15q22), which is involved in the formation, stabilization and remodeling of elastic fibers, and encoding lysyl oxidase. This enzyme is essential for the biogenesis of connective tissue, being an amine oxidase extracellular copper - dependent, which catalyzes the first step in the formation of crosslinks in collagen and elastin. A highly conserved amino acid sequence at the C-terminus seems to be sufficient for the activity of amine oxidase. The N-terminal region is variable and can perform additional functions in regulating development, senescence, tumor suppression, or control cell growth.
Mutations in this gene cause elastin fibers accumulate in the trabecular meshwork, the site by which the intraocular fluid emerging from the eye, preventing said output, leading to an increase in intraocular pressure due to increased pressure intraocular to progressive atrophy of the optic nerve.
Syndrome glaucoma pseudoexfoliation has a pattern of autosomal dominant inheritance, late onset and incomplete penetrance, meaning that one copy of the altered every cell gene is sufficient to cause disruption, but by incomplete penetrance, not all individuals who possess this genetic trait manifested any involvement, hindering the development of family genetic maps.
Tests in IVAMI: in IVAMI perform detection of mutations associated with pseudoexfoliation glaucoma, by complete PCR amplification of the exons of the gene LOXL1 and subsequent sequencing.
Samples recommended: EDTA blood collected for separation of blood leukocytes, or impregnated sample card with dried blood (IVAMI may mail the card to deposit the blood sample).