Deoxyribonucleic Acid (DNA) is served as our genetics instruction and consisted of all the necessary information to build a fully functional human being, living organisms and virus.
DNA contains two strands wrapped around each other in a helix (known as the double helix). Each nucleotide includes 3 parts: a phosphate group, a sugar molecule and one of 4 bases Adenine, Cytosine, Guanine or Thymine.
The backbone of DNA is based on a repeated pattern of a sugar group and a phosphate group. These strands are held in place by one of the four chemicals called bases:
Human Genome has at least 3,000,000,000 (3 billion) nucleotides in sequence. The sequence of nucleotides in DNA and RNA that serve as instruction manual for synthesizing proteins through the process of transcription and translation.
The emerging discipline of nutritional genomics spun out of the Human Genome Project (HGP), the effort started in 1990 by the U.S. Department of Energy (DOE) and the National Institutes of Health (NIH) to identify more than 20,000 genes [chemical base pairs (~3 billion)] that make us who we are. The completion of the HGP has moved a great step forward on the knowledge in gene sequences, particularly in single nucleotide polymorphisms (SNPs). The completion of mapping the entire human genome - are revolutionizing the way we think toward health, illness, and disease prevention. Moreover, it also enable to advances in revolutionizing our understanding of nutrition and how people differ in their response to nutrients.
Nutritional Genomics has benefits of this genetic revolution and it is recognized as a major breakthrough in the nutritional sciences. Nutrigenetics is one of the sub-disciplines of Nutritional Genomics, it is to understand the gene-based differences in response to dietary components and developing nutraceuticals (i.e. health food and supplement) that are most suitable for individuals based on their genetic makeup. This newly developing field of science focuses on the interaction among genes and environmental factors, specifically bioactive components in food and how a person's diet interacts with his or her genotype to influence the balance between health and disease.
On the other hand, another sub-discipline of Nutritional Genomics is known as Nutrigenomics, which aims at understanding how food components influence health status by how chemicals in food affect or altering the expression and/or structure of an individual's genetic makeup. In short, Nutrigenomics reveals how nutrition influence the expression of the genome and Nutrigenetics is to reveals how individual's genetic makeup will response to diet.
" The alarming increase in the prevalence of obesity and associated pathologies points the finger at the mismatch between the modern diet, a sedentary lifestyle and our genetic inheritance. The worldwide epidemic of obesity today affects both adults and children. "
The target of nutrigenetics study became more genome-wide owing much to the success of projects, including the completion of the Human Genome Project (HGP) and the International HapMap Project. The goal of the HapMap Project is to compare the genetic sequences of different individuals to identify chromosomal regions where genetic variants are shared. These genetic differences are known as single nucleotide polymorphisms (SNPs). Each SNP represents a difference in a single DNA building block, called a nucleotide.
For example, a SNP replaced a nucleotide Cytosine (C) with the nucleotide Adenine (A) in a specific region of DNA and its represented as change in the DNA sequence CCGGCTAT to CAGGCTAT.
SNPs could serve for the predication of an individual's response to certain drugs, susceptibility to diet such as fat. SNPs do not cause disease, but they can help determine the likelihood that someone will develop a particular condition.
Nutrigenetic testing (also known as nutritional genomic testing) involves testing for SNPs and other gene variations that may play a role in how an individual responds to diet. When lined up our DNA sequences and compare to others and there are more than 99% identical. That means only 1% of our DNA sequence is unique and SNPs represent the 1% where we differ from each other. In Nutrigenetic testing, these differences influence why some people respond poorly to a particular diet. This does not stop here, scientists are also studying how these SNPs in the human genome correlate with disease and drug response.
Furthermore, genetic polymorphisms in the targets of nutrient action such as receptors, enzymes or transporters could alter molecular pathways that influence the physiological response to dietary interventions. Those SNPs might determine the properties of the proteins coded by certain genes and the affect has on metabolism, transport and assimilation of nutrients in the diet and the effect on elimination of toxins.
In the aspect of well-being, the great challenge of the 21st century will be the integration of the scientific knowledge and provide diet, lifestyle, and drug recommendations aiming for individual preventative purpose rather treating and curing them for the disease and its condition.
Conventional dietary recommendation assumes that all individual are culturally, ethnically, socio-economically and genetically the same but this is not the case. It is apparent that one size does not fit all. As we have become aware of the limitations of population-wide advice such as the food guide pyramid. Therefore, a second generation approaches have been built with pyramids tailored for children, the elderly, different ethnic groups and others.
In a sense, personalized nutrition does already exist, for example cultural preferences, life stage and lifestyle but is not yet relied on genetics information. Today's the power of nutrigenomics and nutrigenetics lies in improving our understanding of diet-gene interactions. The total of these knowledge will be a better understanding of the influence of inheritance and environment on individual health and performance. Here, we added the genetic factor into the weight control equation and aiming to improve the entire outcome.
Using the genetics information, professions could develop a personalized (rather than generic) nutritional advice to individual. Those individual could incorporate such personalized nutritional advice as a basis for their food choices and life style guidance for taking a better control of their own health. In the past, we were at the population-based approach and now moving toward the personalized-based approach.
Please be reminded that nutrigenetic testing is not designed to give a yes or no answer. It is hoping that such test will provide useful information on who is more or less likely to benefit from a particular type of nutrition and lifestyle choices.
The major health problems of the near future will be those of preventable conditions associated with obesity, type-II diabetes and cardiovascular disease. The burden on society of these conditions is already there and is expected to reach near crisis situations over the next 10-20 years. To tackle these coming epidemics healthcare will require an aggressive change from curative to preventative. One of the keys to this will be fostering changes in lifestyle, principally nutrition and physical activity.
According to WHO reports, diet factors influence occurrence of more than two third of diseases. Most of these factors belong to the categories of nutrigenetics and nutrigenomics. In the future both of the nutrigenetics and nutrigenomics, will induce many changes in preventive medicine and also in clinical medicine.
" At the turn of the millennium, the application to nutritional sciences of high-performance technologies associated with genomics catalyzed the emergence of nutritional genomics. In particular, nutrigenomics uses the so-called 'omics technologies' to define and characterize 'dietary signatures' that may reflect the actions of nutrients on the structure and expression of the whole human genome, as well as the final impact on health. These advances have made it possible to look at the interactions between genes and nutrients from a global and systemic perspective. "
Humans are not only genetically different. This highlights the necessary synergies between the genotyping and the systematic biology investigations of the metabolism deploying transcriptomics, proteomics, epigenomics and metabolomics, providing insights into how diet and health alter the expression or 'manifestation' of our genomes.
In the near future detailed tailor-made nutritional recommendations will be possible, taking into account individuals' personal nutritional needs on the basis of their genotype, age, sex, physical activity and profession, the purpose of all this being to improve the population's health. Food personalization is not a new concept and it has been practiced for centuries. However, the emerging scientific basis and industrialization of personalized nutrition and food are new phenomena. Personalized health and scientific nutrition has the opportunity to offer a compelling and cost effective solution to many of today's chronic and acute medical conditions and diseases in the near future.
Progression of knowledge in the fields of nutrient–gene interactions promises a future revolution in preventative health care.