▲ CRITICAL Before assaying the cleavage efficiency of transfected cells, we recommend testing each new SURVEYOR primer on negative (untransfected) control samples for the intended cell type by SURVEYOR nuclease digestion. 71Harvesting cells for DNA extraction. Dissociate all transfected cells (from Steps 13, 29, 53, 65 or 70) and spin them down at 200g for 5 min at room temperature. Keep the replica plates as needed to maintain transfected cell lines in culture.72Aspirate the medium completely.73For DNA extraction, use the QuickExtract solution according to the manufacturer's instructions. We typically use 50 μl or 10 μl of the solution for each well of a 24-well or 96-well plate, respectively.74Normalize the extracted DNA to a final concentration of 100–200 ng μl–1 with ddH2O.
