TECHNOLOGIES APPLIED TO THE MARINE ENVIRONMENT

Module MOLECULAR TRACEABILITY OF FISH PRODUCTS

By the end of the module, students will have acquired a basic understanding of the principles of molecular traceability and authentication of fish products, with particular reference to genetic markers, DNA barcoding, PCR, sequencing and the main molecular databases. They will also be able to understand the main issues relating to species substitution and the authenticity of fish products.

Students will be able to apply the knowledge acquired to solve simple problems relating to the molecular identification of fish species. In particular, they will be able to follow the main stages of a DNA barcoding protocol, from DNA extraction to PCR amplification and the interpretation of electrophoretic results, as well as use simple bioinformatics tools for sequence identification.

Students will be able to critically interpret the results obtained through molecular methodologies, assessing their reliability, limitations and possible sources of error. They will also be able to compare molecular identification with the information provided on a fish product’s label and assess the authenticity of the sample.

The student will be able to describe, using appropriate scientific language, the principles of the main methodologies used for molecular traceability, and to present and discuss the results of an identification analysis. They will also be able to draft a short scientific report on laboratory activities.

Students will have acquired the methodological tools necessary to independently explore topics relating to the molecular identification and authentication of fish products, through the consultation of scientific texts, databases and specialist literature. They will also be able to recognise the main developments in molecular techniques applied to traceability, such as metabarcoding and next-generation sequencing methods.

Students must have a basic knowledge of general biology, genetics and zoology

1. Traceability and authenticity of fish products.

2. Molecular markers and DNA barcoding.

3. From biological sample to sequence.

4. Molecular identification and bioinformatics.

5. Case studies.

6. Laboratory activities: extraction of genomic DNA from processed fish products, PCR amplification, agarose gel electrophoresis.

The written exam consists of 20 multiple-choice questions and 1 open-ended question. Each multiple-choice question is worth 1 mark if answered correctly, and 0 marks if left blank or answered incorrectly. The answer to the open-ended question will be marked on a scale of 0 to 5, taking into account completeness and relevance.

Assessment criteria

The following will be assessed: - knowledge and understanding of the subject matter;

- ability to apply and interpret the material;

- ability to integrate knowledge across disciplines;

- accuracy and appropriateness of scientific language;

- relevance of the answers;

- clarity of presentation.

During a standard thermal cycle of a polymerase chain reaction (PCR), what is the correct sequence of steps and the corresponding indicative temperatures required to ensure the successful amplification of the DNA target?

A. Denaturation (55°C) – Annealing (72°C) – Extension (95°C)

B. Annealing (55°C) – Denaturation (95°C) – Extension (72°C)

C. Denaturation (95°C) – Annealing (55°C) – Extension (72°C)

D. Extension (72°C) – Denaturation (95°C) – Annealing (55°C)