Genetic variation and dietary response: Nutrigenetics/nutrigenomics

Advances in molecular and recombinant DNA technology have led to exquisite studies in the field of genetics and the recognition in a much more specific way, through DNA sequencing, of how unique each one of us is, and the extent to which genetic variation occurs. The importance of the effects of genetic variation has been extensively studied and applied by pharmacologists in drug development and evaluation of drug metabolism and adverse reactions to drugs. In the past two decades, physicians, geneticists, and nutritionists have begun to study the effects of genetic variation and gene–nutrient interactions in the management of chronic diseases, such as coronary heart disease, hypertension, cancer, diabetes and obesity; and the role of nutrients in gene expression. A new era is being ushered in that may be called ‘nutrigenetics/nutrigenomics’. The new genetics has enormous implications for nutrition research both in the prevention and management of chronic diseases. Because families share both genes and environment (in this case, diet), similarity may result from either. Much research has been carried out to define the contribution of each and their interaction in the development of the individual. Knowledge of genetic susceptibility to disease will help identify those at higher risk for disease, as well as their response to diet. The prospect of targeting specific dietary treatment to those predicted to gain the most therapeutic benefit clearly has important clinical and economic consequences, particularly in diseases of high prevalence such as coronary artery disease, hypertension, osteoporosis, and possibly cancer. With the unfolding genomic and technological revolution, continuing investments in research offers unprecedented opportunities to understand disease processes, prevent intrinsic and environmental risks to health and develop new approaches to improve the quality of life worldwide. Furthermore, knowledge of genetic susceptibility to disease will help identify those at higher risk for disease, as well as their response to diet. As a result, there will be a need for the development of novel foods targeted to individuals, families and subgroups within populations. Although the emphasis of new genetics has been on pharmacogenetics, it is the responsibility of the nutrition scientists to expand in parallel the relationship of genetics and nutrition and establish nutrigenetics/nutrigenomics as a major discipline in nutrition in the 21st century.