Association Between Matrix Metalloproteinase-9 Gene Polymorphism and Susceptibility to Primary Open Angle Glaucoma Patients in Sohag University Hospital

Glaucoma is the second most common cause of blindness worldwide. Glaucoma is a progressive optic neuropathy, characterized by a specific loss of retinal nerve fibres and ganglion cells, gradual decrease of the visual field, and vertical elongation of optic disc cupping. Glaucoma causes a slow loss of vision in the centre of the field of view as well as in the periphery. This results in delays in the diagnosis and treatment, and it is likely that the glaucoma may not be diagnosed until the disease has progressed to a moderate or severe level, at which point significant vision loss will have already taken place

POAG is the most common type of glaucoma that is characterized by specific glaucomatous retinal, optic nerve, and clinical findings without a clear secondary cause.

POAG is a progressive optic neuropathy characterized by loss of ganglion cells and deterioration of the visual field in eyes with gonioscopically open angles, either with or without increased intraocular pressure (IOP).

Matrix Metalloproteinase-9 gene Matrix metalloproteinases (MMPs) are a kind of calcium-zinc ion-dependent proteolytic enzyme involved in a variety of cellular processes. MMPs are well known for their ability to degrade the extracellular matrix (ECM) and are involved in several intracellular mechanisms from cell differentiation, proliferation, and angiogenesis to apoptosis.

The MMP genes were suggested to play an important role in the development of various glaucoma types, MMPs are important regulators of the aqueous humor outflow from the eye anterior chamber and therefore significantly affect intraocular pressure. Patients with diagnosed POAG have an altered MMPs level in the aqueous humor.

Several studies have been conducted to analyze polymorphic variants of the MMP for their possible contribution to POAG, Several loci of the MMP genes (rs3918242, rs3918249, rs17576 matrix metalloproteinase-9 were associated with POAG.

Inclusion criteria

• Men and women older than 30 years
• Primary open angle glaucoma as evidenced from characteristic visual field loss and optic disc cupping (POAG group)
• Healthy subjects matched by age, sex and ethnicity to the POAG patients group (control group)

Exclusion criteria

• Exfoliation glaucoma, pigmentary glaucoma
• History of acute angle closure