The Evolution of DNA Typing in Agri-Food Chain

Background: DNA typing has revolutionized not only diagnostics and forensics but also how we can analyze food. A number of techniques have been successfully applied for DNA analysis of plant-derived food. However, unlike forensics, a universally employed method has not yet emerged. Methods: A keyword-based search was performed using the ISI-Web of Science database to look for research articles on DNA testing in agri-food chain. After screening and eligibility check, a Systematic Review was compiled focusing on the techniques used to detect DNA polymorphisms. Results: The collection and summarization of the eligible peer-reviewed empirical studies indicated that PCR-based methods are the predominant technical approach for DNA testing in the agri-food chain. Simple Sequences Repeats are the preferred DNA molecular markers. In recent years, approaches based on DNA-sequencing are expanding, with the DNA barcoding representing the most popular option for species identification. Hypothesis-free NGS approaches are limited. Conclusions: The choice of the method is mainly dictated by the aim of the genetic analysis (e.g., to distinguish plant species or varieties) and the need of quantitative information rather than the features of the food product or beverages. The implementation of new technologies (e.g., NGS-based) is growing but their use remains narrow compared to diagnostics.