This is an observational study where a small skin cell sample or peripheral blood sample will be used to produce iPSCs. After RB1-deficient iPSCs are produced, their karyotype and RB1 mutation will be confirmed and their pluripotency will be tested by studying the expression of pluripotent genes and proteins according to standardized guidelines established for human iPSCs. After validation of the RB1-deficient iPSCs, they will be differentiated in the laboratory into retina following established protocols.