Genome editing to perform cDNA knock-in as a functional gene correction strategy. The figure schematizes the overall strategy and key results of using genome editing to knock-in a WT cDNA to functionally correct downstream mutations. The dashed oval depicts that the TALEN mRNA was delivered into the T cells by electroporation. The dashed gray lines depict HR between the endogenous gene containing a nuclease-induced DSB and the donor vector. 3′ arm, 3′ homology arm; 5′ arm, 5′ homology arm; ATG, endogenous initiation codon; E1-E5, exons 1-5; TCR, T-cell receptor.