My father’s father had a fatal heart attack at age forty. My father had a heart attack and triple bypass at forty and another triple bypass in his sixties. His brother died of a heart attack and his other brother has had a heart attack and triple bypass. So my family history of heart disease is not looking very good at all! But can I expect that I will suffer the same fate, just because it’s in my genes? The answer is, “No, not at all”. We can no longer blame our ill health on our genetics because it’s how we live our lives that really determine whether or not these genes will express themselves.
After the discovery of our genetic material, called DNA (deoxy-ribonucleic acid), we entered an era of genetic determinism, or the belief that DNA is the primary determinant of our individual traits. However, information from the Human Genome Project (completed in 2003 by the U.S. Department of Energy and the National Institutes of Health) has revealed that it’s not all so cut and dry. The Human Genome project found far too few genes (25,000) to account for all the proteins found in the human body (100,000). Single-gene disorders affect less than 2% of the population and diseases such as cancer, heart disease, and diabetes are the result of complex interactions among multiple genes and environmental factors. While it is true that most diseases are linked to genes, genes are not the sole cause. Genes are not self-emergent: they cannot turn themselves “on” and “off”. Genes do not have the ability to “control” life, because they are dependent upon environmental triggers to determine when and how they will be expressed. Enter the filed of epigenetics, or the study of how environment affects genetic expression. Factors such as stress, nutrition, and emotions can modify genes without changing the basic blueprint. Studies of protein synthesis reveal that epigenetic factors can create 2000 or more variations of proteins from the same gene blueprint.
So, while may very well have some aggressive genes for heart disease that predispose me to a heart attack, there are thousands of ways in which these genes may express themselves. And it all has to do with my lifestyle. Yes, if I gain twenty kilograms, smoke fifty cigarettes a day and let every little nuance of stress get to me, then I’m probably going to meet my genetic fate one day. However, if I continue to live a healthy lifestyle, practicing moderation with any bad habits, I will probably never have to suffer the wrath of heart disease. Nurture wins.