Fig. 2.

PCR–RFLP of the pvdhfr gene. PCR–RFLP products of VDF13NF/VDFNR58 with HaeIII showed no cleavage of the 232 bp fragment indicating of wild type Ile13 (a). Reaction with SacII cleaved the PCR products to 138 and 94 bp indicating wild type Pro33 (b). Reaction with AluI cleaved the PCR products to 208 and 25 bp fragments, indicating a mutation 58Arg, while cleavage to 167, 40 and 25 bp indicated a wild type Ser58 (c). Reaction with Tsp451 showed no cleavage (232 bp) indicating a mutation 61Met, while wild type Thr61 showed a cleavage to 200 and 32 bp fragment (d). a, b and d: Lane L DNA ladder of Agilent DNA 1000 Kit (Agilent Technologies, Molecular Probes Inc, USA), Lanes 1–12 PCR–RFLP products of samples. c: Lanes L DNA ladder of Agilent DNA 1000 Kit (Agilent Technologies, Molecular Probes Inc, USA), Lane 1–11 PCR–RFLP products of samples