Related Experiment Video
Updated: Apr 18, 2026
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Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
Published on: November 11, 2016
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Circadian rhythms regulate refractive development across species
Teele Palumaa1,2,3, Nele Taba1, Shruti Balamurugan2
1Estonian Genome Centre, Institute of Genomics, University of Tartu, Tartu, Estonia.
Biorxiv : the Preprint Server for Biology
|April 17, 2026
Summary
Late chronotype is linked to myopia. Disrupting circadian rhythms in mice caused reversible myopia, suggesting circadian misalignment as a modifiable cause of abnormal eye growth.
Area of Science:
- Ophthalmology
- Chronobiology
- Genetics
Background:
- Myopia is a growing global health issue with unclear biological links to modern lifestyles.
- Circadian rhythms are suspected to influence refractive development, but direct causal evidence is lacking.
Purpose of the Study:
- To investigate the causal link between circadian misalignment and myopia development.
- To explore the biological mechanisms underlying this connection using human data and an animal model.
Main Methods:
- Analysis of population-scale data from >265,000 individuals in the Estonian and UK Biobanks.
- Experimental disruption of circadian rhythms in mice using non-24-hour light-dark cycles (T26).
- Retinal transcriptomic analysis to identify molecular pathways involved.
Main Results:
- A consistent association between late chronotype and myopia was observed in human populations.
- Exposure to a lengthened light-dark cycle (T26) induced a myopic shift in mice, which was reversible in early adulthood.
- Retinal transcriptomics revealed enrichment of mitochondrial and hypoxia-related plasticity pathways.
Conclusions:
- Circadian misalignment is identified as a conserved and modifiable driver of myopia.
- These findings suggest novel preventive and therapeutic strategies targeting circadian rhythms for myopia control.
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