Normal tension glaucoma is not associated with the interleukin -1alpha (-889) genetic polymorphism

Factors other than intraocular pressure are likely to play a role in the pathogenesis of glaucomatous optic neuropathy, particularly in individuals with normal tension glaucoma (NTG). Recent laboratory evidence has shown that there are potential similarities between Alzheimer disease and NTG in cellular apoptosis leading to neurodegeneration. IL-1alpha (-889) T allele polymorphism has been found to increase the risk of developing Alzheimer disease. The aim of this study was to test in a Chinese cohort the hypothesis that IL-1alpha (-889) polymorphism is associated with NTG.

One hundred sixty-two unrelated patients with NTG were recruited and compared with 167 controls in a Chinese population. Genomic DNA was amplified by polymerase chain reaction, followed by enzymatic restriction fragment length polymorphism technique. Patients and controls were genotyped for the C/T polymorphism at position -889 of the IL-1alpha gene promoter region.

There was no significant difference in the frequency of IL-1alpha (-889) alleles or genotypes in the NTG population compared with that in the control group.

We conclude that C/T polymorphism at position -889 of the IL-1alpha gene promoter region does not increase the risk of developing NTG. However, further studies on NTG are necessary to investigate the genetic basis and factors involved in the development of the neurodegenerative process.