Proceedings of the XLV Italian Society of Agricultural Genetics - SIGA Annual Congress

Salsomaggiore Terme, Italy - 26/29 September, 2001

ISBN 88-900622-1-5

Oral Communication Abstract

THE TRACEABILITY ALONG THE AGRO-FOOD CHAIN: THE RANGE OF APPLICATION OF MOLECULAR METHODOLOGIES BASED ON GENOMICS, PROTEOMICS AND METABOLIC PROFILING

MARMIROLI N.

Sezione di Genetica e Biotecnologie Ambientali, Dipartimento di Scienze Ambientali, Università di Parma, Parco Area delle Scienze 11/A, 43100 Parma

Tel. 0521/905606; Fax 0521/905665

marmirol@unipr.it

The traceability of proteins and/or DNA (from plants, animals and micro-organisms) in agro-food chain is not only a matter of technique and methodology, but also a scientific and cultural operation between archaeology and paleobiology. Searching among the remains of something, particularly the remains of living organisms, requires attention and precaution including the evaluation of: 1) the origin of the sample; 2) its physical form at the time of the transformation; 3) the environment where the sample originated from; 4) the eventual protective or preserving agents the sample has been treated with; 5) the possibility of accidental contamination; 6) the effect of genetic segregation and gene regulation on phenotypic expression of characters; 7) pre- and post-harvest factors that have modified the phenotype; 8) the quality and the quantity of technical operations carried out on the sample; 9) the matrix effect on the extractability of the target; 10) the randomness and the error in the biological measures.

For those who up until this moment imagine that this was only a matter of technique, the above points, which are only the most important ones, should ring a necessary alarm bell. DNA traceability, which differs from analysis such as HACCP, is a scientific procedure that aims to reconstruct a complex biological picture beginning with the analysis of the more or less "fossil" traces. These traces have been historically sought in three different types of subcellular compounds: metabolites, protein and DNA. With the advent of new molecular and informatic technologies along with the availability of new analytical instrumentation for the analysis of these substances, comprehensive approaches, known as metabolomics, genomics and proteomics have evolved. We are now witnessing the development and diffusion of these approaches with the aim to identify or verify by means of specific analysis the nature and authenticity of raw materials for the production of widespread commercial products including novel foods and animal feed. The range of application of these approaches in the future will concern: i) the labelling of food or food ingredients containing OGM material above the threshold acceptable (or defined) as accidental contamination according to the 2001/18/EC , ii) the evaluation in the field of the efficiency of the containment of gene flow from OGM and wild relatives, and iii) assessing the compatibility between OGM and organic cultivation in a pluralistic agriculture.

These objectives demand the development and implementation of methods essentially based on the PCR such as “Real Time” PCR, “Nested” PCR and semiquantitative PCR (PCR Clamping), and on analysis based on Mass Spectrometry and NMR of metabolic and protein profiles. Such methods permit both a qualitative and quantitative evaluation of the different compounds within a biological sample.

Furthermore, with the aim to develop a rapid method for the simultaneous identification and quantification of a large number of raw materials in the agro-food chain, microarrays based on the application on simple matrixes such as glass of specific sequences (DNA microarray) and antibodies (protein microarray) are currently under investigation.

The analysis of these arrays should allow the rapid identification of the origin of the raw material used to obtain the final product and possible frauds with respect to what has been declared on the label of the same product. Further development in the future of new technologies based on arrays of proteins and DNA should permit the expansion of the idea of traceability also to foodstuff safety.