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Myopia is a refractive error of the eye that is prevalent worldwide. The most extreme form, high myopia, is usually associated with other ocular disorders such as retinal detachment, macular degeneration, cataract, and glaucoma, and is one of leading causes of blindness. The etiology is complex and has not been fully elucidated. In this study, we identified a novel missense variant of the CCDC111 gene (NM_152683.2: c.265T > G; p.Y89D) in a high myopia family by exome sequencing. The variant was identified in 4 patients from an additional 270 sporadic high myopia patients, but not found in 270 controls. The amino acid is highly conserved across species, and variants giving rise to amino acid substitutions are predicted to be functionally damaging. The CCDC111 gene was ubiquitously expressed in primary cell cultures from human eye tissue, including corneal epithelial cells, choroidal melanoma cells, scleral fibroblasts, retinal epithelial cells, retinal Müller cells, and lens capsule epithelial cells. In summary, our results suggested that the CCDC111 may be a susceptibility gene for high myopia. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To determine corneal biomechanical properties in patients with high myopia. Design: Observational study. Methods: High myopia patients (n =45, age: 37.0±12.6 years) with refractive errors of spherical equivalent (SE) greater than −9.00D were recruited in this study along with healthy subjects (n =90, age: 33.7±12.4 years) with refractive errors of SE ranging from 0D to −3.00D. Only the right eye was studied. Central corneal thickness (CCT) was measured by optical coherence tomography (OCT). Metrics of corneal biomechanical properties, including corneal hysteresis (CH) and corneal resistance factor (CRF), were measured with the Ocular Response Analyzer (ORA). The ORA also determined the values of intraocular pressure (IOPg) and corneal compensated IOP (IOPcc). Results: No significant differences of CCT and CRF were present between the two groups (P =.15 and 0.35 for CCT and CRF, respectively); however, CH in the high myope group was lower than that in the controls (P <.01). IOPg and IOPcc were both significantly higher in the high myopes compared to the controls. In both groups, there were significant correlations between CH and CCT and between CRF and CCT. CH was not significantly correlated with age in either the control group or the high myope group (P >.05). There was a significant correlation between CH and SE when the two groups were combined for analysis. Conclusion: CH, but not CRF, was significantly lower in high myopia patients compared to that in normal subjects. The results indicate that some compromised aspects of the biomechanical properties of cornea may exist in people with high myopia. [Copyright &y& Elsevier]