We've Long Known That Humans Carry Neanderthal DNA. Now, We’re Starting to Understand Its Implications

It’s no longer a mystery that humans, especially those of European descent, carry a significant amount of genetic information inherited from our Neanderthal ancestors. However, researchers are gradually uncovering the specific functions that these genes serve in our bodies.

Two recent studies have delved into the legacy of Neanderthal genes in modern humans. The first study focuses on the shape of our noses and suggests a possible connection between the size of this facial feature and Neanderthal genes in certain populations. The second study, for its part, revealed that this genetic inheritance also plays a role in a crucial aspect of our health: our immune system.

Now, let’s dig deeper into what these two studies conclude.

The most recent one was conducted by a team led by researchers from Cornell University. The paper’s authors highlight that Neanderthal genes play a significant role in our immune system. The researchers also observed that more modern genes are gradually replacing them.

The scientists based their work on genetic data from the UK Biobank, obtaining genetic information from nearly 300,000 people. This allowed them to identify over 235,000 genetic variants of potential Neanderthal origin, with more than 4,300 linked to 47 human characteristics such as metabolism, development, and the immune system.

The study was published in the eLife journal. Moreover, the authors made the software used in their research available to the public, as stated by Xinzhu Wei, one of co-authors of the study.

A Specific Gene

The second study, conducted by researchers from University College London, was published in the Communications Biology journal. It focuses on a specific aspect of the genes inherited from Neanderthals: the shape of our noses. In this study, researchers identified 26 regions in the human genetic code that are related to facial features.

One of the genes inherited from Neanderthals is ATF3. Previously, scientists associated this gene with the regeneration of nervous tissues. However, new genetic analysis has discovered that the expression of this gene is controlled by another gene linked to the development of facial features.

Researchers found that this inheritance from Neanderthals wasn't equally widespread in all modern humans, but was more present among Native Americans. This led them to believe that this feature may have been maintained in the Americas for adaptive reasons. After all, Neanderthal genetic traits are more frequent in humans originating in Europe, Asia, and the Americas.

Advances in paleogenetics, or the study of our ancestors’ genetics, have applications in understanding our bodies and our health. Our Neanderthal inheritance not only plays a role in our facial features, immune system, and metabolism. It also affects childbirth.

“More broadly, our findings can also provide new insights for evolutionary biologists looking at how the echoes of these types of events may have both beneficial and detrimental consequences,” Sriram Sankararaman, one of the authors of the Cornell paper, said.

Depending on our origin, the Neanderthal inheritance in our genome can range from 1% to 4%. Therefore, it’s important to understand the genetic inheritance passed down by our closest human cousins in order to understand our own bodies. We can thank these ancestors for many of the traits that make us human and have allowed us to survive to the present day.

Image | Pixabay| Werner Ustorf [CC BY-SA 2.0]