Correct gene targeting verified by sequencing. The correct 5' and 3' targeted boundary of one rAAV-mediated BRCA1 KO cell clone (5D1) was validated by sequencing. This BRCA1 KO cell clone has been used as nuclear donor cells for somatic cell nuclear transfer to generate BRCA1 KO pigs (Luo et al. Transgenic research 2010). Sequencing was performed with the primers P1 and P2.