Diet–Gene Interactions: Haptoglobin Genotype and Nutrient Status

Abstract

Many disease states are independently influenced by both diet and genes. Dietary and genetic factors can also act synergistically to have a joint effect on human health through diet–gene interaction. For example, the protein products of genes (enzymes, transporters, receptors, hormones, etc.) may interact with nutritional constituents of foods to influence metabolic processes and health status. Commonly occurring polymorphisms in the genes that code for these protein products can lead to differences both in the amount of protein produced and in how efficiently that protein functions, thus leading to individual differences in processes such as digestion and metabolism. Among researchers and healthcare practitioners, there is a growing interest in utilizing genetic information to predict and manage the large interindividual differences in response to intake of food and nutrients. Recent advances in human genomics have enabled cost-effective and rapid detection of variations in genes affecting nutrient metabolism, but their full impact on nutrient requirements remains to be elucidated. The common haptoglobin polymorphism is an example of a polymorphism which may have an important influence on chronic disease via its impact on nutrient status. The objective of this chapter is to introduce the concept of diet–gene interactions and to discuss the various effects that genes can have on metabolic responses to food, focusing on the common haptoglobin polymorphism as an example.