Blame it on your genes
“Blame it on the rain (rain)……Blame it on the stars(stars)……Whatever you do, don’t put the blame on you….”, went a famous blockbuster song of 1990.It very beautifully summarizes the attitude of human beings who have always looked for some scapegoat to blame for the misery of their own making. God, destiny, stars, weather have all taken the blame sometime or the other. The latest to join this illustrious rank is our genome.
It has become fashionable to blame all our health and behavioral issues on our genes. From obesity, cancer, Alzheimer’s, lying, stealing, bad heart, inability to exercise all are blamed on the genes without fully understanding how genes express themselves. It is possible to alter genes.
How genes express themselves?
DNA or deoxyribonucleic acid is the hereditary material located in the nucleus of every cell of our body. DNA functions through indivisible units called genes. Each gene contains a particular set of instructions, usually coding for a particular protein or for a particular function. DNA is around six feet long and in order to fit into a minuscule nucleus of a cell, it wraps itself around clusters of the protein called histones in a form of a molecular spool. This resulting combination of DNA and histone is called chromatin.
Epigenetics marks: The way to access and alter genes
While wrapped structure or chromatin solve the packaging problem, it makes it difficult to access genes. Nature has designed a complex chemical tagging system to make gene accessible. These chemical tags sit on top of the chromatin and provide instructions whether to make a gene accessible or not. Since these tags sit outside the DNA, they are called epigenetic or instructions that are outside of our genes. When these tags condense the chromatin, they obscure the underlying genes and prevent them from expressing themselves. In other words, these genes are turned off. On the other hand, when these chemical tags de-condense the chromatin the genetic information becomes available to the cell and the genes are said to be turned on. These types of epigenetic marks are profoundly influential to our biology. They help to alter genes. It is these instructions that help undifferentiated cells of a few days old fetus to develop into specialized tissues and body parts of a baby.
Epigenetic Marks and Environment
One important aspect of epigenetic marks is that they get influenced by the environment and this is not limited to the environment surrounding the cell but the environment we are exposed to like our diet, lifestyle, physical exercise, exposure to pollution. These influences become more pronounced in embryos where the mother’s lifestyle directly impacts their development. Mother’s nutrition, stress levels, lifestyle during pregnancy get transmitted to the fetus as chemical signals or epigenetic marks and lay the foundation for child’s long-term health consequences. In adults also lifestyle and diet can help to switch on the good genes while keeping the bad genes unexpressed.
Is there a direct link between genes and diseases?
It is seen that though the identical twins share the same DNA, they develop different diseases and conditions during their life. The fact that 99.9 percent of our genome is similar to that of our neighbor suggests that it is way too simplistic to blame our genes when we get sick. Though there are a few monogenic diseases like cystic fibrosis, sickle cell anemia, Huntington that can be attributed to a defect in a single gene, most of the chronic diseases are the result of a complex interaction between various genes and environment. No clear pattern or direct correlation has yet emerged for the scientists to suggest genetic interventions. Genetic predisposition is one part of the story the other part is our lifestyle, environment, and our biome. Genes just load the gun but it is the environment that pulls the trigger.
We have more bacterial genes than our own!
Further, for every one human gene, we have 100 associated genes of bacteria, viruses, protozoa and fungi microbes that live in our gut, mouth, skin and other mucosal surfaces of our bodies. These microbes perform vital functions in digestion, metabolism, fighting the disease-causing pathogens and synthesis of essential nutrients and vitamins. They regulate our mood and influence the impact of certain medicines on our bodies. Changes in the microbiome can trigger changes in human cellular activities, resulting in disease or contribute to its progression. Microbiome also affects the expression of genes. A study at the University of Wisconsin-Madison has shown that good bacteria helps to switch on good genes while bad bacteria can either switch off good genes or express the bad ones.
Health is an interplay of many factors
Thus, it is not our genes that are the culprit for all our health malaise. Health is a result of a very complex process involving our genome, biome and external stimuli we give to our bodies by way of food, lifestyle, stress, pollution, social environment, climate etc. The fact that we can alter our genes through epigenetics is very empowering as it provides us with an opportunity to take charge of our health. Epigenetic changes happen throughout our lives and our choices can make real differences in how our health shapes up. It is never too late to start eating right, exercising, reducing stress and meditating. So even though we are defined by our genes we have a degree of freedom that can help us to create a life of health and vitality.
Ancient healing practices such as Ayurveda, Yunani, Siddha emphasize on the holistic approach to health aiming at creating an ecosystem where our genes and environment are in harmony with each other.