Example 9
Leaf tissue is collected from clonal plants separated for transplanting and analyzed as individuals. Genomic DNA is extracted using a Wizard® 96 Magnetic DNA Plant System kit (Promega, U.S. Pat. Nos. 6,027,945 & 6,368,800) as directed by the manufacturer. Isolated DNA is PCR amplified using the appropriate forward and reverse primer.
PCR amplification is performed using Hotstar Taq DNA Polymerase (Qiagen) using touchdown thermocycling program as follows: 96° C. for 15 min, followed by 35 cycles (96° C., 30 sec; 58° C.-0.2° C. per cycle, 30 sec; 72° C., 3 min and 30 sec), 10 min at 72° C. PCR products are verified for concentration and fragment size via agarose gel electrophoresis. Dephosphorylated PCR products are analyzed by direct sequence using the PCR primers (DNA Landmarks, or Entelechon). Chromatogram trace files (.scf) are analyzed for mutation relative to the wild-type gene using Vector NTI Advance 10™ (Invitrogen). Based on sequence information, mutations are identified in several individuals. Sequence analysis is performed on the representative chromatograms and corresponding AlignX alignment with default settings and edited to call secondary peaks.