1. The Impact of Ancient Genes on Modern Medical Conditions
The largest genetic database of ancient humans has provided new insights into modern medical conditions such as multiple sclerosis (MS) and the reasons for variation among people in heritable traits. The research indicates that genes behind MS may have become more common due to their role in helping people resist infections passed on from animals.
2. The Genetic Waves of Migration
The genes of people with ancestry from Europe and west Asia have been shaped by three large waves of migration, including modern humans, farmers from the Middle East, and livestock herders from the Eurasian steppe. These migrations have had a significant impact on the genetic composition of modern populations.
3. Genetic Risk for Multiple Sclerosis
The research team analyzed bone and teeth samples from nearly 5000 ancient remains to understand the impact of mass movements on modern medical conditions. They found that individuals with a higher genetic risk of MS have more ancestry from the Yamnaya people, and some of the MS-predisposing genetic variants first arose in this population.
4. Genetic Risk for Alzheimer’s Disease
The study also shed light on how ancestry affects genetic risk for Alzheimer’s disease. People with more ancestry from the first hunter-gatherer populations of Europe are more likely to have a gene associated with a higher risk of developing Alzheimer’s. An alternative variant of this gene, which gives protection against Alzheimer’s, arose in the incoming Yamnaya people.
5. Understanding Selective Pressures
The research emphasizes the importance of understanding the selective pressures that influenced the prevalence of certain genes in ancient populations. It highlights the need to consider the impact of ancient environments on genetic traits and their potential advantages or disadvantages.
6. Height Variations in Europe
Among people living in Europe, those with more Yamnaya ancestry tend to be taller. This finding may explain the variation in average stature between people in northern and southern Europe.
The research on ancient human genes has provided valuable insights into the genetic basis of modern medical conditions and heritable traits. It has highlighted the long-term impact of ancient migrations on the genetic composition of modern populations and the potential influence of ancient genes on resistance to infections and other conditions. This study underscores the importance of considering the historical context and selective pressures when studying genetic traits and their implications for modern health.
Researchers have discovered that genes associated with multiple sclerosis may have evolved to protect humans from ancient animal-borne infections. By studying the genetic variations in populations with different levels of exposure to livestock, the study found that certain genes linked to multiple sclerosis were more prevalent in populations with a history of livestock-related infections. This suggests that these genes may have developed as a defense mechanism against such infections, shedding new light on the origins and potential mechanisms of multiple sclerosis.