A protocol for the efficient screening of putatively transformed plants for bar, the selectable marker gene, using the polymerase chain reaction

Amplification of the bar gene using Tag DNA polymerase in PCR is often not successful, possibly due to bar's high GC content. We describe a PCR protocol in which reliable amplification at a sensitivity of one gene copy per genome (in this study, barley) present in the reaction was achieved using a novel pair of primers and Expand(TM) High Fidelity DNA polymerase mix (Boehringer Mannheim). This method should allow for rapid screening of plants putatively transformed with bar.