ZFN constructs specific for the rat C3 gene were designed to target bases 1803-1841 (NCBI reference sequence: NM_016994) of C3 (target sequence: cagggggcccgagtgggctagtggctgtggacaagggg) by Sigma-Aldrich (Tokyo, Japan). The ZFN systems were injected into the pronucleus of SHR/Izm embryos. The DNA of 10 day old pups was extracted and screened for ZFN-induced mutations. Briefly, DNA extracted from ear tissue was amplified using primers flanking the target sequence (forward primer: 5'-ACTCTTCCCTGTCTTGCGTC-3'; reverse primer: 5'-AATAGAGGCCACCAATGCAC-3'). This mutant revealed a 9-base frameshift deletion of bases 1815-1824 (ggctagtgg).