OTX2 and infection: To explore mechanisms underlying the abnormal differentiation of photoreceptor cells induced by lentiviral vectors, we first analyzed the expression patterns of photoreceptor fate-determining genes following lentiviral infection, and found an up-regulation of photoreceptor fate-determining genes (OTX2, CRX, PRDM1, RAX, RXRG and PHLDA1, etc.)[21–23] (Fig. 2D, Supplementary Fig. 4).