The application of DGGE and AFLP-derived SCAR for discrimination between Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss)

In an attempt to authenticate commercial frauds in fresh products of Atlantic salmon (Salmo salar) by being adulterated and substituted with those of rainbow trout (Oncorhynchus mykiss), two molecular tools, AFLP (amplified fragment length polymorphism) and DGGE (denaturing gradient gel electrophoresis) were explored here. A species-specific SCAR (sequence characterized amplified region) marker for rainbow trout (O. mykiss) was developed based on AFLP analysis. In addition, DGGE was utilized to discriminate Atlantic salmon (S. salar) from rainbow trout employing a fragment of the mitochondrial cytochrome b gene. Analysis of experimental mixtures demonstrated that the detection sensitivity of AFLP-derived SCAR is higher than that of DGGE. In order to ascertain commercial frauds are fabricated by the adulteration or substitution of rainbow trout, DGGE analysis of cytochrome b gene should be combined because only one species-specific SCAR just for rainbow trout was obtained in this study.