For most complex diseases like diabetes and cancer, or heart disease, it's an interchange between genes and environment that gives rise to disease. You may be predisposed in a certain way by genetics, but you're probably not going to get the disease unless the environmental trigger is present, too. So it is extremely important to understand how the genes and the environment work together and how we can modify the environment for individuals whose genetic susceptibilities indicate that they're at risk. The observation that genetically identical twins often vary greatly in observable traits related to diseases clearly shows that gene-environment interaction is an important regulator of variation related to a number of diseases. Genes are vulnerable to modification in response to toxic stress, nutritional problems and other negative influences and other environmental factors that both genes and environment can affect disease propensity not just separately, but through direct interaction with each other.
The blog below provides insight into the different traits impacted by genes due to change in genetic expression caused in response to various environmental factors.
Your genotype decides your propensity level of developing oxidative stress. Oxidative stress is the imbalance between the production of free radicals or reactive oxygen species (ROS) and antioxidants. An excess of ROS can lead to the oxidation of proteins, lipids, carbohydrates, and DNA which can cause damage to tissues and organs, and subsequently several disorders such as diabetes, atherosclerosis, inflammation, cancer, and neurodegenerative diseases. The number of free radicals or reactive oxygen species in the body can increase due to influences from environmental factors.
Genes involved - Near SOD3, SOD3, SOD2
Your genotype decides your propensity level for developing an imbalance in the detoxification process. Having a balance between the different detoxification phases is important to ensure the metabolism of reactive oxygen species and other toxic agents which can make us susceptible to many diseases. Factors such as diet, lifestyle habits like drinking and smoking, environmental triggers, and underlying diseases may increase the risk of developing an imbalance of detoxification activities.
Genes involved - GSTO1, GSTP1
Your genotype decides your propensity level for developing an imbalance in the methylation process. Methylation is a mechanism in which a methyl group is added to a DNA segment, without changing its sequence. This mechanism is used by the cells to control gene expression and modify the functions of the gene. Methylation plays a crucial role in gene expression, affects embryonic development, and regulates development. Any error or imbalance in the methylation of the DNA contributes to the risk of developing several diseases and destructive consequences. Various lifestyle, environmental, and dietary factors can influence the methylation process.
Genes involved – MTRR, CBS, MTR
Your genotype decides the inflammatory response your body exhibits to invaders and threats or even post an exercise session. However if our body experiences constant stress, this can lead to too much inflammation which can eventually lead to organ damage. Exercise tends to damage muscle cells, thereby eliciting an inflammatory response. This inflammatory response repairs the muscle and aids in its growth and adaptation. If there is an up-regulation of the body's inflammatory enzymes, it can possibly lead to greater inflammation and hence greater muscle soreness. Chronic inflammation can put us at greater risk for things like cardiovascular disease, diabetes, asthma, and even depression and dementia.
Genes involved – CRP, IL6, Near TNFA
Most of the changes are observed at cellular levels and the impact is visible only when a person starts showing symptoms for diseases. Deciphering the epigenetic changes triggered by environmental factors (including current lifestyle and nutrition) through genomic profiling paves the way for personalized nutritional interventions and aids our understanding of how our bodies respond to specific diets or nutrients and what changes need to made in lifestyle for achieving sustainable health outcomes.
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