Near-Isogenic Lines as Powerful Tools to Evaluate the Effect of Individual Phytochemicals on Health and Chronic Diseases

The growing epidemic of chronic diseases in the twenty-first century has emphasized the importance of developing staple crops with enhanced nutritional value and health benefits. Plant-based diets are associated with reduced risk of many chronic diseases, which are partially due to the health-promoting effects of enriched phytochemicals. Despite the great effort put into understanding the effectiveness of phytochemicals through epidemiological and human intervention studies, the results are inconclusive. Phytochemicals used in these studies, and other cell or animal-based models, are often purified compounds and not the whole-food matrix. Emerging evidence suggests that the food matrix can significantly influence phytochemical stability, bioavailability as well as bioactivity. However, the studies where whole foods are used could encounter difficulties in dissecting out contributions of specific phytochemicals from a mixture of nutrients. Near-isogenic lines (NILs), whose genetic backgrounds differ only in one or a few genes offer feasibility to study for developing whole foods that vary in a specific class of phytochemicals, making them powerful tools. This chapter focuses on reviewing the importance of using NILs in studying the effect of individual phytochemicals in the whole-food matrix to provide evidence-based staple crops to counter the growing epidemic of chronic diseases globally.