Nutrigenetics

Nutrigenetics aims to identify how genetic variation affects response to nutrients. This knowledge can be applied to optimise health, and prevent or treat diseases. The ultimate aim of nutrigenetics is to offer people personalized nutrition based on their genetic makeup.

Due to naturally occurring mutations humans differ in their DNA, which is callled variation or polymorphism of DNA. The most common type of DNA polymorphism are SNPs (short for “single nucleotide polymorphism”). SNPs may influence the way individuals absorb, transport, store or metabolize nutrients. This may determine requirements for different nutrients and this assumption forms the basis for nutrigenetic sciences. Moreover, different metabolic potential of the human body can imply an advantage in terms of natural selection. For that reason, for example, the ability to digest lactose, the principal sugar of milk, also in adulthood spread in cattle-rising populations.

The identification of the necessary genotype is carried out by means of a blood analysis or a cheek swab. Subsequently, the DNA is analyzed in different ways. A common way to study the genetic data is the so-called “candidate gene approach” when one possible risk gene is identified. After experiments on cell cultures, animals or humans scientists can establish a positive or negative correlation between the expression of this candidate gene and nutritional aspects. Another popular scientific method is a genome-wide association study which also leads to the identification of relevant gene variants. In particular, nutrigenetic analyses are based on the effect of nutritional components on the genome, proteome, metabolome and transcriptome.

A major goal for nutrigenetic researchers is to identify genes that make certain individuals more susceptible to obesity and obesity-related diseases. The thrifty gene hypothesis is an example of a nutrigenetic factor in obesity. The thrifty gene theoretically causes bearers to store high-calorie foods as body fat, a most likely as an evolved protection against starvation during famines. However, the potential "thrifty genes" that may be affected by nutritional factors have yet to be identified. Future advancements in nutrigenetics research may potentially prove the existence of thrifty genes as well as find counter-effects in order to prevent obesity and obesity-related diseases.

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Wikipedia