The human genome today isn’t a pure thread of Homo sapiens—it’s a complex tapestry woven with ancient history. Hidden in the DNA of many modern people lies a genetic echo from a long-extinct cousin: the Neanderthal.
These archaic humans roamed Europe and parts of Asia until around 40,000 years ago. During their time of overlap with early Homo sapiens, interbreeding occurred. As a result, many people today—especially of European ancestry—carry between 1% and 4% Neanderthal DNA.
As genetic research advances, scientists are uncovering how this ancient inheritance influences everything from our appearance to our immune response. Some traits we once chalked up to random variation may actually be gifts—or burdens—from our Ice Age ancestors.
Here are seven surprising traits that might hint at a Neanderthal legacy in your DNA. While only a genetic test can confirm it for sure, these clues offer a fascinating look at how our evolutionary past still shapes us today.
1. A Long, Prominent Nose
Neanderthal influence might be hiding right in plain sight—on your face. Specifically, in your nose. Rather than width or roundness, the telltale trait is nose length.
Neanderthals evolved in cold, dry climates, and a longer nose helped warm and humidify the air before it reached the lungs. If your nose noticeably extends from bridge to tip, it could be a relic of that cold-weather adaptation—passed down from ancestors who mingled with these hardy humans.
2. Sensitive or Problematic Skin
Not all inherited traits are beneficial. Some Neanderthal genes are linked to rough, scaly skin patches known as actinic keratoses, often triggered by sun exposure. These patches are usually harmless, but they can develop into skin cancer if left untreated.
Additionally, certain immune-related genes from Neanderthals may raise the risk of autoimmune conditions like lupus, Crohn’s disease, and even Type 2 diabetes. These may reflect a mismatch between ancient immune defenses and our modern environment.
3. Thick Hair and Tough Nails
On the brighter side, your glossy hair or strong nails might also have a Neanderthal connection. Some ancient genes are linked to increased keratin production, the protein that gives hair, skin, and nails their structure and strength.
This was likely a survival advantage for Neanderthals, helping protect against the elements. There’s also a curious link between Neanderthal DNA and red hair—a rare and eye-catching trait still seen today.
4. Heightened Risk of Severe COVID-19
One of the most surprising discoveries during the COVID-19 pandemic was a link between Neanderthal DNA and a higher risk of severe illness. A specific gene variant—found in about 16% of Europeans—seems to influence immune response in a way that worsens outcomes.
What once may have helped fight off ancient pathogens may now trigger an overreaction to modern viruses. It’s a powerful example of how evolutionary adaptations can have unintended consequences in a very different world.
5. A Strong (But Overactive) Immune System
Some Neanderthal-derived genes do boost immunity, offering better resistance to bacterial, fungal, and parasitic infections. But there’s a trade-off.
These genes may also contribute to allergies, thanks to an immune system that reacts too aggressively to harmless stimuli like pollen or pet dander. Essentially, the same ancient defense mechanisms that once helped early humans survive can now cause sneezing fits and itchy eyes.
6. A Predisposition to Nicotine Addiction
While Neanderthals certainly didn’t smoke, some modern humans with Neanderthal gene variants seem more likely to become addicted to nicotine.
The connection likely lies in genes that affect the brain’s reward and motivation systems—once useful for survival-driven behaviors like hunting and gathering. Today, those same systems may increase vulnerability to addictive substances.
7. Brainpower with Ancient Roots
Forget the old stereotype of Neanderthals as slow or dim-witted. Research now shows they had brains as large—or in some cases, larger—than modern humans, along with complex tools and cultural behaviors.
One gene, microcephalin, plays a key role in brain development and may have entered the modern human gene pool through Neanderthal interbreeding. Some scientists believe this gene helped shape our cognitive evolution. If you’re particularly sharp or a quick problem solver, your ancient ancestors might deserve some of the credit.
8. Sensitivity to Pain
Neanderthal genes may influence how we experience pain—literally. One inherited gene variant affects ion channels in nerve cells, potentially making some people more sensitive to physical discomfort.
Researchers have found that individuals carrying this ancient variant often report feeling pain more intensely than those without it, especially in response to heat or pressure. While this sensitivity might seem like a drawback, it could have once helped early humans avoid injury or detect danger more quickly.
9. A Natural Night Owl
Struggle to fall asleep early? Your Neanderthal genes might be to blame. Some ancient DNA variants are associated with circadian rhythm differences, making people more prone to being night owls.
In prehistoric times, this could’ve been a useful trait for keeping watch after dark or hunting under moonlight. Today, it might just mean you’re more alert at midnight than in the morning meeting.
10. A Broad, Barrel-Shaped Ribcage
Your chest shape could also hold clues. Neanderthals had broad, barrel-shaped ribcages and wider pelvises—adaptations that likely supported large lungs and helped conserve body heat in frigid environments.
Some modern humans have inherited elements of this body structure, which can give the torso a more cylindrical or stocky appearance. It’s another physical marker that might tie you to ancient ancestry built for survival in harsh climates.
The Past Is Still With Us
The traces of Neanderthals within us go beyond anthropology—they’re personal. From our appearance to our health to our behavior, the distant past lives on in our genes. While not all traits are visible or beneficial, they remind us that human evolution wasn’t a straight path, but a shared journey with other human species.
Curious to find out your own connection? A DNA test can provide the full story—but even without it, these signs offer a fascinating glimpse into the legacy of a long-lost relative.