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U.S. Department of Health and Human Services


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RFE Tutorial


A description of RFE "Pages" or Information Containers


The Web Implementation of the Regulatory Fish EncyclopediaPage Image Example
The Seafood Products Research Center (SPRC), SEA-DO, SAN-DO, and CFSAN have collaborated to create the Regulatory Fish Encyclopedia (RFE). The RFE, as a government service, uses the Internet and the graphical World Wide Web to provide information and tools to assist with fish species identification within and outside of FDA.

The RFE is built upon the concept of the highly expandable "RFE PAGE" as information container. An RFE PAGE is dedicated to a combination of pictorial, textual, graphical and numerical data for the theme of that page. For instance, RFE PAGE 0, General Browser, shows the top page of the RFE and links to available fish species.
RFE 0:
General Browser
RFE Tutorial General Browser Page image
The RFE Website pairs fish images with biochemical "fingerprint" patterns. This can assist the public, private and educational sectors, as "Internet Consumers" of the RFE. American consumers potentially lose millions of dollars per year due to seafood economic fraud through species substitution. The use of the RFE and it tools and information for specise identification can help to reduce these fraudulent practices and save consumers money. By publishing the encyclopedia on the Web, the RFE information is easily available a large audience readership at a reduced cost to the government.

In this frame, RFE PAGE 0, Species Specific Browser to Pacific Cod (Gadus macrocephalus), indicates links to the various information pages available for this species.
Example: Pacific Cod
Species Specific Browser
RFE Tutorial Specific Browser Page image
RFE PAGE 1a contains high quality images (drum scanned from high quality 4" x 5" photographic transparencies) of finfish in the round: thumbnail images on the page and large and small images (jpg format) linked from the page.RFE PAGE 1a:
Pacific Cod in the Round
RFE Tutorial Page 1a Whole Fish image - Pacific Cod
RFE PAGE 1b contains large and small images of market product forms (including fillets and/or steaks, and whole animals, where applicable, (e.g. crab) are available.

Marketed Product Form examples
Pacific Cod Fillets
RFE Tutorial Page 1b Fish Fillet image - Pacific Cod
RFE PAGE 2a provides general information for the species including geographical distribution, nomenclature variation, associated health risks in Fish and Fisheries Products Hazards and Control Guidance (Fourth Edition; 2011, Seafood HAACP Program) and other miscellaneous market information.

Internally, the RFE is a quick way for FDA scientists and inspectors to compare species in the lab and the docks to authentic specimens by their physical appearance and biochemical fingerprints for inference and deduction in economic fraud investigations. This is particularly useful when only fillets are available in the lab for identification.
Nomenclature and General Information
RFE Tutorial Page 2 Nomenclature and General Information image
RFE PAGE 2b provides detailed taxonomic information for the some species. In this example, details are provided for head size and proportion. Features that are unique to the species are provided to aid in species identification.RFE PAGE 2b:
Taxonomic Information
RFE Tutorial Page 2b Taxonomy - Fish head image
RFE PAGE 3 provides species-specific biochemical pattern information: Mitochondria DNA Sequences from an approximately 650 base-pair region of the CO1 gene. The aligned sequences constitute "barcodes" that can be used to determine the ndentity (usually to the species-level) of the fish in question. The Barcoding project is being carried out as a cooperative effort with the Center for Veterinarian Medicine and the Center for Food Safety and Applied Nutrition in FDA, and the Barcode of Life/FishBol project at the University of Guelph, Ontario, Canada.RFE PAGE 3:
DNA Sequence Data - Barcoding
RFE PAGE 4 provides species-specific biochemical pattern information: Isoelectric focusing (IEF) protein patterns for the pH range 3-10 for fresh, frozen, uncooked seafood based on AOAC 980.16 (a detailed data stamp on each gel image reflects the experimental conditions).RFE PAGE 4:
PAGplate IEF
RFE Tutorial Page 4 IEF Gel image - Pacific Cod
RFE PAGE 5 contains numerical and graphical tools used to examine IEF protein fingerprint patterns. Potential substitutions are confirmed from protein patterns for selected species using graphical and numerical tools for pattern matching between specimen patterns. For a graphical representation of the layout of an IEF gel for the RFE, see "Anatomy of a Gel".

Through the RFE project, FDA also maintains a National Fish Tissue Collection for the acquisition of authentic species tissue samples used in validation experiments in the lab. The RFE site is cross-linked with the FDA Seafood List which provides US FDA approved market names for Seafood.
Calibrated Gel
RFE Tutorial Page 5a IEF Calibrated Gel Page image
Similar Species Comparison
RFE Tutorial Page 5b IEF Comparison Gel image