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Updated: May 14, 2026
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The Rodent Model of Nonarteritic Anterior Ischemic Optic Neuropathy (rNAION)
Published on: November 20, 2016
Genetic polymorphisms associated with endothelial function in nonarteritic anterior ischemic optic neuropathy
Tsutomu Sakai1, Keigo Shikishima, Masato Matsushima
1Department of Ophthalmology, Jikei University School of Medicine, Tokyo, Japan. tstmski@jikei.ac.jp
Molecular Vision
|February 13, 2013
Summary
A specific gene variant in endothelin-1 (ET-1) is linked to an increased risk of developing nonarteritic anterior ischemic optic neuropathy (NAION). This ET-1 G/T polymorphism may be a significant risk factor for NAION in Japanese individuals.
Area of Science:
- Ophthalmology
- Genetics
- Cardiovascular Research
Background:
- Nonarteritic anterior ischemic optic neuropathy (NAION) is a leading cause of irreversible vision loss.
- Endothelial dysfunction is implicated in the pathogenesis of NAION.
- Genetic factors influencing endothelial function are potential contributors to NAION risk.
Purpose of the Study:
- To investigate the association between genetic polymorphisms in key endothelial function genes and the risk of developing NAION.
- Specifically examine endothelin-1 (ET-1), angiotensin-converting enzyme (ACE), and methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms.
Main Methods:
- A case-control study comparing 34 NAION patients with 102 healthy controls.
- Genotyping for ACE I/D, MTHFR C677T, and ET-1 Lys198Asn polymorphisms.
- Statistical analysis to compare genotype distributions and assess risk factors.
Main Results:
- No significant differences in ACE or MTHFR genotype distributions were found between NAION patients and controls.
- A significant difference in the ET-1 Lys198Asn genotype distribution was observed (p=0.009).
- Individuals with the ET-1 TT genotype had a significantly higher likelihood of developing NAION (OR=4.43, p=0.015).
Conclusions:
- An increased prevalence of the ET-1 G/T polymorphism (Lys198Asn) was identified in patients with NAION.
- This ET-1 gene polymorphism is suggested as a potential risk factor for NAION development.
- Findings highlight the role of genetic predisposition in NAION, particularly within the Japanese population.
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