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Myopia, commonly referred to as nearsightedness, is one of the most common causes of visual disability throughout the world. It affects more people worldwide than any other chronic visual impairment condition. Although the prevalence varies among various ethnic groups, the incidence of myopia is increasing in all populations across globe. Thus, it is considered a pressing public health problem. Both genetics and environment play a role in development of myopia. To elucidate the epigenetic mechanism(s) underlying the pathophysiology of high-myopia, we conducted methylation profiling in 18 cases and 18 matched controls (aged 4–12 years), using Illumina MethylationEPIC BeadChips array. The degree of myopia was variable among subjects, ranging from −6 to −15D. We identified 1541 hypermethylated CpGs, representing 1745 genes (2.0-fold or higher) (false discovery rate (FDR) p ≤ 0.05), multiple CpGs were p < 5 × 10−8 with a receiver operating characteristic area under the curve (ROC-AUC) ≥ 0.75 in high-myopia subjects compared to controls. Among these, 48 CpGs had excellent correlation (AUC ≥ 0.90). Herein, we present the first genome-wide DNA methylation analysis in a unique high-myopia cohort, showing extensive and discrete methylation changes relative to controls. The genes we identified hold significant potential as targets for novel therapeutic intervention either alone, or in combination.

Cystic fibrosis (CF) is the commonest multisystem genetic disease of white races, caused by mutations in the cystic fibrosis transmembrane regulator (CFTR), encoded on the long arm of chromosome 7. Mutations in the CFTR gene result in defective sodium, chloride, and water transport in the epithelial cells of the respiratory, hepatobiliary, gastrointestinal, and reproductive tracts, the pancreas, and the eye. The pathogenesis of ocular changes in CF is still unknown, but CF belongs to the large pathologic group of ocular surface epithelial diseases, termed keratoconjunctivitis sicca (KCS), that develop in dry eye syndrome. The aim of this study was to evaluate the levels of macrophage inflammatory protein-1alpha (MIP-1alpha) in the tear fluid of CF patients. We also investigated the correlation between the tear levels of this chemokine and clinical severity of CF and ocular surface disease. We studied 25 patients with CF with a mean age of 14 years. Chemokine levels were determined by ELISA. Complete ophthalmic examination, including dry eye tests, were used to study the ocular surface. The tear levels of MIP-1alpha in the CF patients were significantly higher when compared with healthy controls. We found a negative correlation between the tear levels of MIP-1alpha and clinical severity in CF patients and a positive correlation between the tear levels of MIP-1alpha and the presence of dry eye findings in CF patients. This current study indicates that chemokines play an important role in the ongoing inflammatory response. Our findings may help to explain one of the key factors contributing to the pathogenesis of ocular surface changes in CF patients.

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Purpose: To measure retinal thickness and retinal nerve fiber layer thickness using optical coherence tomography in patients with myopia. Patients and Methods: Thirty patients (13 girls and 17 boys) 14 to 18 years old were included in the study. The control group consisted of 15 patients. Each patient was subjected to routine ophthalmic investigations, which included the assessment of visual acuity for near and distant objects, autorefractometry, measurement of intraocular pressure, biometry, and assessment of the static visual field. The foveal retinal thickness and the peripapillary nerve fiber layer thickness were measured using optical coherence tomography. Results: The mean foveal retinal thickness was 231.0 µm in eyes with low myopia, 218.0 µm in eyes with medium myopia, and 178.0 µm in eyes with high myopia. The mean thickness of the retinal nerve fiber layer was 150.0 µm, 140.0 µm, and 152.0 µm, respectively. Statistically significant differences were revealed between patients with high myopia and the control group. Conclusion: Optical coherence tomography can be employed to assess the retinal thickness and thus facilitate the detection of the evolution of alterations in myopia. J Pediatr Ophthalmol Strabismus 2004;41:159-162.