Whole-eye OCT imaging of refractive errors in genetically modified zebrafish

Refractive errors, such as myopia and hyperopia, are a major cause of visual impairment worldwide. The genetic basis of refractive errors is becoming increasingly understood, and the zebrafish has emerged as a powerful model organism for studying these disorders. In this study, we present evidence that establishes a connection between the mammalian connexin-36 (Cx36) ortholog gjd2b/Cx35.1, a key component of electrical synapses in zebrafish, as well as connexin-27(Cx27.5), and the occurrence of refractive errors. We investigated the morphological and behavioral changes in adult zebrafish. To assess these changes, we utilized a custom-developed 1310nm optical coherence tomography system for analysis of the entire eye. This analysis revealed development of hyperopic shifts in Cx35.1 knockouts, primarily due to a reduction in eye axial length, while no refractive anomalies were observed in Cx27.5 knockouts.