New research suggests that ancient DNA has had a significant impact on the health of modern Japanese individuals. A study conducted by researchers analyzed the genomes of over 170,000 people across Japan and compared them with prehistoric Japanese and Eurasian genomes. The study focused on how DNA inherited from the Jōmon people, who were hunter-gatherers living in Japan thousands of years ago, may be linked to various traits in modern Japanese populations.
The researchers found that on average, Japanese individuals have inherited around 12.5% of their DNA from Jōmon hunter-gatherers. Of all the traits studied, BMI was the only trait significantly associated with Jōmon DNA. Individuals with more genetic evidence of Jōmon ancestry were more likely to have a higher BMI, putting them at a higher risk of obesity.
BMI, while commonly used as a measure of body fat, may not always accurately reflect an individual’s health status. However, a high BMI has been linked to various health risks, including type 2 diabetes. The study also examined people of Japanese ancestry living abroad, such as those in the U.K., and found similar links between Jōmon ancestry and BMI.
The researchers described their findings in a paper published in the journal Nature Communications, highlighting the role of natural selection in shaping the health of modern populations. They theorized that traits beneficial in the past, such as increased BMI, could pose health risks in a modern context.
The study also shed light on the genetic diversity of modern Japanese populations, challenging previous theories about their origins. While it was long believed that modern Japanese people descended from Jōmon hunter-gatherers and migrants from Northeast Asia, recent evidence suggests a third ancestral group from East Asia also contributed to their genetic makeup.
These findings have important implications for understanding the health disparities among different populations and may help explain why some individuals are more prone to obesity than others. The study co-author, Shigeki Nakagome, emphasized the significance of ancient hunter-gatherer ancestry in shaping modern populations’ health and called for further research in this area.
Overall, this research underscores the complex interplay between genetics, ancestry, and health outcomes in diverse populations. It opens up new avenues for exploring the impact of ancient DNA on modern health and highlights the need for more studies to unravel the mysteries of human evolution and genetic diversity.
