Recent research from the Karolinska Institutet suggests that genetic remnants from Neanderthals play a measurable role in modern human physiology. A study published in Current Biology identifies a specific version of the growth hormone receptor that originated from interbreeding with Neanderthals roughly 47,000 years ago.
Laboratory tests reveal that cells carrying this specific receptor variant respond more effectively to growth hormones. These cells showed 40 percent more growth compared to those with the modern human receptor. This discovery bridges the gap between ancient evolutionary traits and observable biological functions in today's population.
The prevalence of this genetic marker varies significantly across different geographic groups. It is most common in South and East Asia, where nearly 24 percent of the population carries the variant. In contrast, it appears in only 0.5 percent of Europeans. While the impact on muscle mass is modest—averaging an additional 0.6 pounds—it highlights the persistent influence of ancient DNA on physical development.
Researchers noted that these biological effects typically manifest during puberty when growth hormone levels increase. Beyond muscle mass, carriers often exhibit physical traits linked to Neanderthals, including shorter lower jaws and tooth roots. Despite these findings, experts emphasize that genetics is only one factor in body composition. Training and environment remain the primary drivers of physical development, regardless of one's genetic background.