If differences between hiPSC lines are indeed more pronounced at earlier stages, it would be very interesting to analyze the expression of genes essential for determining neuronal and retinal fate (e.g., OTX2, PAX6, RAX, or VSX2) at the cyst level, and determine if the lines that are shown to be more efficient and perform better (e.g., 5A) have an earlier and perhaps more stable expression of such genes. The gene discussed is VSX2; the disease is cyst.