PCR

The analytical methods contain the following steps:
1.- Extraction of DNA:
It is necessary to extract the genetic material free from other impurities which might interfere in further steps of the analysis.

2.-PCR reaction ( Polymerase Chain Reaction)
The PCR reactions are suited to multiply and amplify specific fragments of DNA that are alien genes to the food being analysed.

The primer starter molecules used in the beginning of the reaction decides which sequence of DNA will be multiplied.

To avoid false negative results due to inhibit action of impurities during extraction of the DNA it is important to include a positive reaction.

3.-Making the PCR product visible Through gelelectrophoresis (agarosegelelectrophoresis).

The products of the PCR reaction can be made visible together with the determination of the length of the base pair, the alien gen.

4.-Confirmation of the results

The confirmation of the results are being made by controlling the sequence of the base in the PCR product using specific sequence restriction, hybridization with specific sonde Nested PCR and Sequencing The basic PCR gives only qualitative indications.

To obtain quantitative results the Competitive PCR or the RT-PCR should be used