A heart attack at a young age is everybody’s worst nightmare and these days it seems to be happening often. We have all heard the stories friends, family and celebrities who die in their 40s and ’50s due to sudden heart attacks. Some of them would appear perfectly healthy and in fact lead healthy lifestyles as well. We assume that if we exercise regularly, have a balanced diet, and avoid smoking we are safe from heart attacks. But this is not always the case and many people with healthy habits too end up victims of a heart attack.
Then what explains this increasing trend of young heart attack victims. It’s all in our genes! All of us inherit some variations in our genes that have been passed on from our parents and ancestors. Some of these variations have a clear and present danger for certain diseases such as cancer e.g. the mutation in the BRCA gene puts women at high risk of developing breast and ovarian cancer. These risks are easy to identify and most medical practices have already incorporated screening for these risks in their population. But when it comes to diseases such as diabetes and coronary artery diseases (CAD) there is no single gene or a small group of genes that we can examine to say that a person is at high risk. They are caused by multiple small changes in different parts of the genetic code and when these changes come together, they cause disease.
But scientists have been working on this problem and they are slowly getting to a point where they can estimate a person’s risk by measuring all these small variations in multiple sites in the genetic code and adding them together to giving a score. The term Polygenic Risk Score (PRS) is something that is going to be heard more often going forward as it is a culmination of the efforts of genetic scientists to put a number to the risk of a person developing a disease. A person’s PRS number will soon become a reference for their risk of developing a disease. Since this number is dependent on an individual’s genetic makes up it can be measured just once at any point in a person’s lifetime even from his/her birth.
The PRS concept although still in its early stages of development has already been validated for CAD and is close to 90% accurate. It classifies an individual into high, medium, and average risk of developing CAD. Those who are classified as high risk need to take extra precautions to monitor their heart health and possibly start on medication at a much earlier age than the rest of the population. Those who are classified as average risk are not completely off the hook since they need to continue maintaining a healthy lifestyle and diet to avoid getting CAD.
The era of preventive healthcare is upon us and it promises to reduce the number of people developing CAD and diabetes. PRS for CAD shows a lot of potential in preventing the deaths of our near and dear ones much before their time.