Effect of BMP4 treatment on eye size and shape. (A) Retinal volume in BMP4-treated and contralateral BSA-treated eyes estimated from four post-culture embryos and represented by bar charts as mean ± 1 S.D. p = 0.033 by the paired t-test indicates a significant reduction in retinal volume in BMP4-treated eyes. (B, C) Coronal sections of control (B) and contralateral BMP4-treated (C) eyes stained with H&E and showing a reduction in eye size and retinal thickness upon BMP4-treatment. Scale bars: 0.05 mm.