PDE6B and retinitis pigmentosa 1: In postnatal P6 and P10 mice, we found a similar increase in ferritin and active β-catenin protein levels in the rd1 mice retinas compared to WT retinas (Supplementary Fig. 1a, b), indicating that rd1 mouse model of RP has iron accumulation and associated increase in retinal Wnt signaling even before the photoreceptor degeneration starts at P10, thereby implying a contributory role for iron in the progression of RP.