Written by: Brian Chen , PhD, MPH
Most people have heard of genetics . It has received a lot of attention, especially since the race to sequence the first human genome first began. The ongoing discussion on the use of genetic testing for life insurance has re-emerged in recent months. But what about epigenetics ? First of all, what is it? And how does it differ from genetics, particularly in the context of life insurance?
Genetics is the study of your genes, the blueprint for life – eye color, hair color, facial features, etc. Your genetics are inherited from your parents and are hardwired. This part of the field has been under study since Gregor Mendel first took note of differences in traits of peas in 1866, even before James Watson and Francis Crick published their seminal work on the structure of DNA in 1953.
As we approach the twentieth anniversary of the completion of the first draft of the human genome , it’s become clear that genetic sequencing has not wiped disease off the planet, in the news conference held to announce the first draft was completed in June of 2000. Don’t get me wrong. Science would not have progressed to where it currently is without the Human Genome Project, but the fact remains that the scourge of cardiovascular disease and cancer still dominate as the leading causes of death , according to the Centers for Disease Control. In a totally separate line of thinking, some people noticed that every cell in your body has the identical genetic code – that’s why a cheek swab is sufficient to sequence one’s genome – yet one’s liver cells and brain cells look and function differently. How is that possible if genetics is the end-all? Many scientists saw these facts long ago and began to look beyond the genetic sequence.
Epigenetics is one direction in which scientists have looked. The term “epi” literally translates into “above” or “beyond.” In a nutshell, epigenetics is an umbrella term for chemical groups that attach to DNA, RNA, and proteins to alter how genes are expressed, as far as we know now. Your body has layers of regulation and redundancies to keep you physiologically “normal,” and epigenetics is one of those important layers that regulate which genes get turned on or off and at the right time. Imagine what would happen if all the genes in the body were turned on all the time!
Research has shown that epigenetics plays an important role in normal biological function. In addition, it serves as a conduit through which environmental stimuli (e.g., life events or dietary exposures ) translate into a language that your cells can understand and react to on a molecular level. More important, because it has direct applicability to business practice, epigenetics can be used to estimate one’s “biological age.”
What is “biological age,” exactly? It’s ill-defined, but we know that we all age at different rates. Some 60 year olds have the physiology of 40 year olds, while other 60 year olds may be on their deathbeds. Chronological age gets us part of the way, but something is going on in the human body that may be able to better explain why some die earlier or later (or remain healthier) than others.
In 2013, Dr. Steve Horvath at the University of California, Los Angeles (UCLA) demonstrated that powerful statistical models can take epigenetic data, specifically DNA methylation, and estimate one’s biological age . While others have correlated levels of certain molecules in blood to chronological age, to my knowledge, nobody had directly estimated it, especially from molecules attached to DNA, rather than free-floating molecules in blood. We then sought to determine whether this estimated age was capturing biological age, at least in part. And, to the extent that being associated with different rates of mortality suggests biological aging, we found that “ epigenetic aging” was associated with mortality .
What does this mean for industry? Currently, epigenetics cannot be edited like genetic sequences can, so targeted interventions are not yet a possibility. However, predicting mortality can be useful in the life insurance industry. Additional areas that have recently emerged include consumer wellness products using the epigenetic clock and cancer screening using blood samples. The latter has emerged as a powerful new approach that could only be done using epigenetics, and not genetics, as has been done for several decades. The hope is that not only can early signs of cancer be detected, but we’d also be able to read which tissue the cancer is in. This may provide a bounty for healthcare, insurance, and testing companies.
It's so early in this game and many more technologies and research findings will emerge. But with both science and technology moving at a breakneck speed, it is key for businesses to find ways to keep up.Dr. Brian Chen is chief science officer of Life Epigenetics, a wholly owned subsidiary of GWG Holdings. Dr. Chen was first author of the study on DNA methylation and mortality prediction building on Dr. Steve Horvath’s work at UCLA that was published in the journal Aging in September 2016.