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, as promised once the first draft was completed in 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 Center for Disease Control’s leading causes of death. Furthermore, several additional observations suggest that the contribution of knowing one’s genetic sequence has been exaggerated. First, 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. It is also true that people often carry genes for conditions that never occur. How are these things possible if genetics is the end-all? Many scientists saw these facts 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 molecules that attach to DNA, RNA, and proteins to alter how genes are expressed. 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!
Table of differences between genetics and epigenetics.
|Fixed at birth?||Yes||No|
|Source||Inherited from parents||Influenced by environmental factors and aging|
|What it includes||Genetic sequence (A,T,C,G)||Molecules that attach to DNA or RNA|
Research has shown that epigenetics plays an important role in normal biological function. In addition, it may serve as a conduit through which environmental stimuli (e.g., life events or dietary exposures) translate into molecular changes, which in turn, may affect health.
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 age. Then, in 2016, an international team of researchers led by myself and Dr. Horvath subsequently determined that “epigenetic aging”—the difference in your estimated age versus chronological age—was capturing some aspect of biological aging, as indicated through differential rates of 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, the more precise underwriting enabled by epigenetics offers the prospect of revolutionizing traditional insurance underwriting. Additional areas that have recently emerged include consumer wellness products using the epigenetic clock and cancer screening using blood samples (“liquid biopsies”). The latter has emerged as a powerful new approach that could only be done using epigenetics, and not genetics, as has been the approach used for decades. The promise is that not only can early signs of cancer be detected, but also which tissue the pre-cancer is in. This may provide a bounty for healthcare, insurance, and testing companies.
It’s early in this game and many more technologies and research findings are emerging. But with both science and technology moving at breakneck speeds, it is key for businesses to find ways to keep up with these important advances!
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.