So, you’ve discovered where your ancestors lived. What’s next?

Note: This blog was originally published on the Helix Blog. At the moment, my html chops are only so-so. In order to see this blog in its full glory, I strongly recommend navigating to its original home here.

There can be a tempered excitement that comes over a person when they’re about to see their genetic ancestry test results. On the one hand, you know that there’s a limit to how much these tests can tell you, because there is more to ancestry than DNA alone. But on the other hand, it’s a unique opportunity to learn about the history of your DNA and the people you inherited it from. What might that history tell you?

In many cases, people seek out ancestry testing to add some depth to their family history. DNA testing cannot tell you the whole story, but it can help you learn where some of your ancestors may have lived thousands of years ago. The basic principle works like this: Everybody’s DNA is a patchwork, made up of millions of DNA segments that were passed down from previous generations. Within those segments are markers—specific locations in the DNA sequence that can vary from person to person—in which one variant appears more often in certain parts of the world compared to others. Based on the markers present in your DNA, scientists can develop an estimation of where your many ancestors may have lived.

But that’s not all that’s hidden away in your DNA. There have been many important moments in the history of our species that have left lasting marks on our DNA—some of which may still be affecting us today. One such moment is the meeting between Neanderthals and Homo sapiens.

Neanderthals were a group of humans who lived on the Eurasian continent for hundreds of millenia. Approximately 100,000 years ago, Homo sapiens (otherwise known as anatomically modern humans) expanded beyond Africa [1]. Exactly when they came into contact with Neanderthals is unknown, but what we do know is that they mated. As a result, Neanderthal DNA was passed along with Homo sapiens’ DNA into subsequent generations of people. Tens of thousands of years later, many people still carry DNA derived from Neanderthals in their genome, representing genetic heirlooms passed down from their distant Neanderthal ancestors [1].

Neanderthals vs. Homo sapiens

In this article we’re referring to Neanderthals as a group separate from Homo sapiens, but this is actually a bit of a simplification.

In reality, Neanderthals are a subspecies of Homo sapiens—as are we! The proper name for what we call “Neanderthals” in this blog is Homo sapiens neanderthalensis. Likewise, the proper name for anatomically modern man—what we simplify to “Homo sapiens” in this article—is Homo sapiens sapiens.

So what does it mean to have inherited Neanderthal DNA (or, inversely, to have not inherited it)? This is the question Insitome can help you explore in a product aptly named Neanderthal. Going beyond just reading how much Neanderthal DNA you may have inherited, Insitome explores how that DNA may be influencing some of your traits. Researchers studying introgressed DNA—the DNA passed to us from Neanderthals and other archaic human groups—have found that some segments of Neanderthal DNA are associated with the way a person’s body stores and synthesizes fat, or the way their body recognizes certain pathogens [1]. Scientists are still working out how (and to what extent) Neanderthal DNA may affect people’s traits. Insitome lets you take advantage of this early research to look into your past in a fresh, new way.

But that’s not all that your DNA can tell you about your ancestors. Approximately 11,000 years ago, humans began to farm. This cultural revolution swept the globe, leading many civilizations to transition from a primarily hunter-and-gatherer way of life to a farming economy. This caused a radical change in diets and in the environments that people lived in. Over time, this change led to an increase in frequency of some genetic marks—marks that have been passed on to modern people. A good example of this can be found in the MCM6 gene. A change in the DNA sequence for this gene influences whether a person can digest lactose (a sugar found in dairy products) as an adult. Once humans began to domesticate cattle in northwestern Africa, Europe, and in the Middle East, specific variants in the DNA that allowed people to consume dairy as adults became more widespread within these populations [2]. You can learn about this trait—and more—with Insitome Metabolism.

People tend to think of ancestry testing simply as a way to get a numerical breakdown of where your ancestors may have lived in the past—but there’s so much more! What might your DNA tell you?

References

1. Nielsen, Rasmus et al. “Tracing the peopling of the world through genomics” Nature vol. 541,7637 (2017): 302-310.

2. Gerbault, Pascale et al. “Evolution of lactase persistence: an example of human niche construction” Philosophical transactions of the Royal Society of London. Series B, Biological sciences vol. 366,1566 (2011): 863-77.