Species substitutions revealed through genotyping: Implications of traceability limitations and unregulated fishing

Abstract

Trade flow of fisheries sector is very complex with several intermediaries and it is difficult to trace back the origin of a seafood commodity. Thus, traceability limitations could cause safety and quality issues in the final product delivered to the consumers. Decreased monitoring may also increase the possibilities of illegal, unreported and unregulated fishing practises. In global fisheries sector, a proper species identification system for identifying and preventing commercial frauds like species misrepresentation and illegal trade is mandatory. DNA analysis is a promising technique for food authentication as it provides increased specificity, sensitivity and reliable performance for accurate specimen identification and species confirmation. Mitochondrial cytochrome c oxidase subunit I gene (mtCOI) fragments represent one of the robust genetic marker for identification of specimens up to species level. It is a stable genetic marker which could be amplified from fresh, degraded, processed or cooked materials. India is having very limited regulations for preventing improper labelling of seafood items and ensuring authentication for traded fish and fishery products. This study focuses on the applicability of DNA barcodes over fish and fishery products traded at different sectors like local markets, supermarkets, restaurants etc. Samples collected from different stations of Ernakulam district (Kerala, S. India), were subjected to molecular analysis and COI sequences were developed. Among the 62 samples, 34 samples were identified as species substituents and the substitution rate was accounted up to 54.84%. In addition, trade of certain exotic/invasive and illegally cultured species were also confirmed. This study discusses the applicability of DNA barcoding in fisheries sector for preventing food fraud and suggests its implementation as a systematic regulatory programme conducted by governmental agencies for fishery stocks authentication.