Evaluation of DNA markers for fish identification

Abstract

Species substitution is a common commercial fraud, mainly applied to fish species. It is thus important to have analytical methods for species identification. DNA analysis can be a suitable technique: some mitochondrial genes are actually recognized as valuable markers for species discrimination. Aim of this work was thus to evaluate the capability of cytb and COI genes to discriminate the species of fish (n=89) which are commonly substituted. In the last four years of activity on field, the laboratory analysed, using the FINS method (Forensically Informative Nucleotide Sequencing), 146 samples, belonging to several fish species, sent by veterinary officers in the frame of their activities of control: in this work, results about number and kind of fraud are reported. Additionally, samples directly purchased by the lab were examined. The obtained results showed that the genetic markers have a high discriminatory power and that the method is highly suitable. The frequent detection of species substitution in the samples collected on field showed the importance of controlling this kind of frauds in the fish market

Fish species identification in canned pet food by BLAST and Forensically Informative Nucleotide Sequencing (FINS) analysis of short fragments of the mitochondrial 16s ribosomal RNA gene (16S rRNA)

“…For the aforesaid reasons, and considering that the feed producers are all concentrated along the coast of Thailand, is highly unlikely that the species E. purpurea and E. oligobranchus were used in the products analyzed in this study. Moreover, the presence of E. devisi in a sample commercialized in Italy as S. pilchardus has already been reported (Riina et al, 2012).…”

A Rapid Method for the Identification of Fresh and Processed Pagellus erythrinus Species against Frauds

“…Fraudulent substitution of the common pandora occurs not only when prepared and processed specimens have lost external characters but also as whole fish, due to the morphological resemblance with other sparid species (e.g., Pagellus acarne , Pagellus bellottii , Pagrus pagrus , Lutjanidae spp.) [ 9 , 10 , 11 , 12 , 13 ]. Currently, cytochrome b- Cytb , cytochrome c oxidase I- COI , 16S , and 12S genes of the mitochondrial (mt) DNA are traditionally used for fish species identification [ 14 , 15 , 16 ].…”