Studies focusing on the RPE have been largely limited to the chick model, with a consistent finding across a series of studies undertaken by Zhang et al. being the early, bidirectional regulation of Bmp2, which was found to be rapidly downregulated with the initiation of myopia-inducing treatments (both form deprivation and imposed hyperopic defocus) and rapidly upregulated under conditions that slow eye elongation, such as those created by the termination of myopia-inducing treatments [24,25,39]. Here, BMP2 is linked to myopia.