Today, it is not uncommon to discuss the etiology of human disease in the context of genes, environment, and nutrition. With the sequencing of the human genome and the rapid scientific advances in technology that followed, researchers have been able to explore the linkage between diet and those molecular processes that govern long-term health and disease outcomes.
The role of genomics has replaced the earlier emphasis placed on genetics and heredity, since hereditary transfer assumes to be assured in genetic deficiency diseases, while genomics accepts the individual variation and asks why. While the presence of a particular gene variant may indicate a predisposition to a particular disease, such as obesity, hypertension, type 2 diabetes mellitus, cardiovascular disease and cancer, the expression of those phenotypes will depend on the complex interplay between external factors and the molecular components that regulate expression of specific genes. The genes involved in each of these phenotypes are also shared in expression amongst the diseases resulting in metabolic syndrome and varied forms of cancer. The challenge is to identify the mechanisms by which gene expression can be regulated and controlled.
The Single Nucleotide Polymorphism story has been exciting for the past 5-7 years, indicating single nucleotide transformations altering protein structure, and is still being studied. However, the nutritional genomics story has changed as new analytical tools have allowed evaluation of gene networks, enabling identification of regulatory control points, and has stimulated assessment of bioactive agents in various locations within the cell to affect signal pathways and metabolic balance.
Previously, the role of diet and nutrition focused only on solving essential nutrient deficiencies and counting calorie sources, and ignored other components of foods. In recent years, many non-nutrients have been identified as bioactive food components (currently studied as function foods) as they affect disease onset by altering gene expression.
Genomic and nutritional researchers must reconcile the diverse properties of dietary signals with our current knowledge of regulatory gene networks that control the higher order disease traits. In addition to increasing our understanding of the inherited basis of disease, the maternal diet and environment may set epigenomic (post transcriptional) gene changes in the embryo that are expressed later in the life of the offspring. Nutritional genomics also provides the promise to revolutionize the way we manage health and disease risk with genome based dietary recommendations and other lifestyle changes.
With this understanding will come opportunities to develop nutritional interventions and dietary recommendations that will enable individuals to achieve optimal health earlier, and maintain it longer, with evidence-based nutritional genomic diets. The ultimate goal will be to use selective whole foods in our diet to prevent some of the catastrophic health outcomes currently overtaking our children and impacting their future health and longevity. This focus on personalized nutrition will have important implications for the agricultural and food industries, affecting how they can create and deliver the needed products.