Altered ocular parameters from circadian clock gene disruptions

Area of Science:

• Ophthalmology
• Chronobiology
• Genetics

Background:

• The pathophysiology of refractive errors, particularly myopia, is not well understood.
• Myopia blurs vision and increases the risk of blinding eye diseases in adulthood.
• Emerging evidence links ambient light exposure and diurnal variations in eye dimensions to refractive development.

Purpose of the Study:

• To investigate whether disruptions in circadian signals affect the refractive development of the eye.
• To explore the role of clock genes in ocular development and refractive error.
• To determine if circadian dysregulation is a potential mechanism underlying myopia.

Main Methods:

• Investigated the effect of retinal-specific knockout of the clock gene Bmal1 in mice.
• Examined the impact of knocking out clock genes (cycle, period) in Drosophila melanogaster.
• Assessed changes in ocular dimensions, specifically the vitreous chamber and pseudocone.

Main Results:

• Retinal Bmal1 knockout in mice induced myopia and elongated the vitreous chamber, mimicking clinical myopia.
• Knocking out Drosophila clock genes lengthened the pseudocone, affecting optical development.
• Disrupting circadian signaling altered eye optical development in both mice and fruit flies.

Conclusions:

• Circadian dysregulation is proposed as a mechanism contributing to myopia development.
• These findings suggest a conserved role for circadian signaling in eye optical development across species.
• Addressing circadian dysregulation may offer novel therapeutic strategies for myopia in children.