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The present study investigated the ability of DNA barcoding to reliably identify the seven commercially important salmon and trout species (genera Oncorhynchus and Salmo ) in North America. More than 1000 salmonid reference samples were collected from a wide geographic range. DNA extracts from these samples were sequenced for the standard 650 bp barcode region of the cytochrome c oxidase subunit I gene (COI). DNA barcodes showed low intraspecies divergences (mean, 0.26%; range, 0.04-1.09%), and the mean congeneric divergence was 32-fold greater, at 8.22% (range, 3.42-12.67%). The minimum interspecies divergence was always greater than the maximum intraspecies divergence, indicating that these species can be reliably differentiated using DNA barcodes. Furthermore, several shorter barcode regions (109-218 bp), termed "mini-barcodes", were identified in silico that can differentiate all eight species, providing a potential means for species identification in heavily processed products.

Fish and seafood substitution has become an important concern in domestic and international marketplaces, in part due to increased international trade, per capita seafood consumption, and production of processed foods. In many cases, seafood substitution is a form of economic deception, where highly prized species are substituted with those of lesser value. To prevent illegal species substitution, a number of DNA‐based methods have been developed to detect fish and seafood species in commercial products. These methods, along with common gene targets, have been reviewed previously in this journal. The current article is meant to build upon earlier discussions by providing a comprehensive review of the application of these DNA‐based methods to the discovery of fish and seafood substitution on the commercial market. Popular food uses, potential substitution cases, and peer‐reviewed research articles published to date are discussed for all major species groups of concern, including flatfish, gadoids, scombroids, salmonids, percoids, sturgeons, sharks, eels, and bivalves. The use of DNA‐based methods to monitor commercial whale meat products is also reviewed.

Although capture fisheries have experienced slow to stagnant growth in recent years, the world population has been increasing, with subsequent rises in demands for marine‐based foods. One possibility for alleviating potential food shortages and price increases is through aquaculture, which has experienced rapid worldwide expansion. A major focus of research in the aquaculture industry is on the use of biotechnology to increase food availability and reduce production costs, specifically through the manipulation of the genes and chromosomes of cultivated species. Examples include transgenic fish with properties such as increased growth rates, feed conversion efficiency, disease resistance, cold tolerance, and improved metabolism of land‐based plants. However, use of transgenic organisms in aquaculture is a very controversial topic due to a number of environmental and human health concerns such as escapement and introduction of genetically modified organisms into the food chain. In response, some transgenic research has also been focused on inducing sterility to reduce the risk of transgenic organisms breeding with wild species. A method of chromosome manipulation, referred to as polyploidy, provides the option of creating sterile organisms, some of which also exhibit increased growth rates. This review paper will discuss recent advances in biotechnology research, specifically in regards to the manipulation of genes and chromosomes, for enhanced cultivation of fish and invertebrates. Major environmental and human health concerns will also be addressed.