Real-time PCR assay for pangasius DNA detection and the possibilities of its use for fish products control

Real-time PCR assay for detecting the Pangasiidae family DNA in fishery products using real- time polymerase chain reaction has been developed in order to identify fraudulent activities such as the substitution of more valuable fish species with pangas. The method is based on the multiplex PCR to identify the 16S rRNA fragment specific to Pangasiidae family with simultaneous amplification of endogenous internal control. The method demonstrated 100% specificity when examining the control panel of various fish samples. The absolute sensitivity limit was 100 copies per reaction. The method is applicable to raw minced and filleted fish, as well as multicomponent products and processed samples. 111 samples of fish products were selected from various retail outlets in Moscow and the Moscow region and tested using the method. Pangasius DNA was found in five of the samples, which had not been declared on the product labels. Discrepancies were found in two samples of “Dori fillet”, a sample of “Sea tongue fillet”, a cod cutlet and a crab sticks. The possibilities of using this method to control the correctness of labeling of fish products are discussed.