Abstract
<jats:p>This chapter covers the underpinning terminology and understanding of genetics and inheritance. It considers the areas of dietetic practice, including the evidence base and challenges with respect to advertising some aspects of nutrigenetics and personalised nutrition. Single‐gene conditions are caused by a mutation in one particular gene or pair of alleles that affects the production or function of its resulting protein. Multifactorial conditions are caused by the additive effects of minor alterations in many genes, combined with environmental factors. Gathering a multigenerational family history is a useful tool for healthcare professionals, including dietitians. Nutritional genomics is the application of the interaction between genetics, genomics, diet, nutrition and other environmental factors, specifically in relation to the maintenance of health and the prevention of disease. The use of metabolomics in personalised nutrition is a potentially powerful approach that could help professionals and individuals tailor dietary recommendations based on an individual‐s unique metabolic profile.</jats:p>