Protein- and DNA-based methods have been developed to identify fish species recently introduced into the German market. By means of isoelectric focusing (IEF) of sarcoplasmic proteins, characteristic protein patterns were obtained for pangasius (P. hypophthalmus), yellow fin sole (Limanda aspera) and arrowtooth flounder (Atheresthes stomias).
In case of pangasius and yellow fin sole a ~460 base pair segment of the cytochrome b gene was amplified by PCR and sequenced. Restriction fragment length polymorphism (RFLP)- and single strand conformation polymorphism (SSCP)-analysis of three genes (cytochrome b, immunoglobulin heavy chain constant region, trypsinogen) demonstrated the possibilities of rapid identification of P. hypophthalmus.