 What are the origins of Indo-European DNA and are they part of your genetic heritage? In one of my last videos, I looked at some of the properties of Indo-European DNA and have it spread across Eurasia with the expansion of various archaeological cultures, most notably the Yamnaya culture of the Pontic Caspian steppe, with many other cultures related to the Yamnaya, such as the Cordyde Ware culture. In this video, I want to look at the genetic origins of the Yamnaya people themselves and the steppe ancestry they spread. It's not all good news, however, and at the end of this video, I will discuss how the spread of Yamnaya DNA across Eurasia may have increased the chances of developing a debilitating disease. Now on a high level, genetic studies have suggested that the people of the Yamnaya culture can be modelled as a genetic admixture between a population related to Easter and hunter-gallerers and people related to hunter-gallerers from the Caucasus, with additional admixture from Anatolian, Levantine or early European farmers. The Yamnaya are considered Western and steppe herders. Haplogroup R1B, specifically the Z2103 subclad of R1B L23, is the most common YDNA haplogroup found amongst the Yamnaya specimens. Now let's look at this in a little more detail. A study published earlier this year in Nature looked at the population genomics of post-glacial Western Eurasia. The authors begin by noting that Yamnaya ancestry, that is steppe ancestry, has been characterised broadly as a mix between Easter and hunter-gallerer ancestry and Caucasus hunter-gallerer, formed in a hypothetical admixture between a northern steppe sauce and a southern Caucasus sauce. However, the exact origins of these ancestry sources have not been identified. To get more detailed results, they studied the genomes of 1600 ancient people and found that the steppe ancestry composition can be modelled as a mixture of around 65% ancestry related to hunter-gallerer genomes from the Middledon River region and around 35% ancestry related to hunter-gallerers from the Caucasus. Thus, Middledon hunter-gallerers who already carried ancestry related to Caucasus hunter-gallerers serve as a hitherto unknown proximal source for the majority ancestry contributing to the Yamnaya related genomes. Therefore, the majority of the steppe or Yamnaya related ancestry stems from a group of hunter-gallerers who lived around the Don River region in modern-day Russia, close to the border with Ukraine, who lived there around 7,500 years ago. Now that we know a little more about the genetic origins of the Yamnaya people, what modern populations of Europe are most closely related to the Yamnaya? Well, a study from 2015 touched on this aspect. If we look at this table from the study, we can see that Norwegian people have the highest Yamnaya-like ancestry, followed by Lithuanian, Estonian, Icelandic and then Scottish people. Imagine that! The Declaration of Arboroth, one of the most famous documents in Scottish history written in the 14th century, says that the Scots were originally from Greater Scythia, which is an area just north of the Black Sea where the Yamnaya lived thousands of years ago, and the genetic research seems to suggest there is actually some truth to this. As is often the case, origin stories usually have seeds of truth in them. But what features did the Yamnaya bring with them? Before that, if you value this content, please consider buying me a coffee or supporting this channel on Patreon. All the links will be in the description below. Thank you and now on with the video. Now, the spread of steppe-related ancestry across Europe, through the Yamnaya culture and other associated cultures, probably increased the height of Europeans. A study looked at this, the impact of the Indo-European migrations, on Neolithic Denmark. And the results indicate an increase in height, consistent with ancient steppe individuals being predicted taller than average European Neolithic individuals before the steppe migrations. Now, height is generally considered a good thing, but it wasn't all rosy. There is emerging evidence that the Yamnaya migration, along with associated migrations across Eurasia, introduced new genetics that increased the chance of a certain disease developing. Multiple sclerosis, or MS, is a neuro-inflammatory and neuro-degenerative disease that is prevalent in all in Europe. This map shows a general geographical pattern of the risk of MS developing, with blue and red being high risk and is quite closely correlated with countries which have strong Indo-European ancestry, or who are descended from these populations at least, i.e. a lot of people in America and Canada have European ancestry. Now, a study published in Nature earlier this year looked at how the elevated genetic risk for MS emerged in steppe-pastoralist populations. They found that the genetic risk for MS rose amongst pastoralists from the Pontic steppe and was brought into Europe by the Yamnaya-related migration approximately 5,000 years ago. They further show that these MS-associated immunogenetic variants underwent positive selection both within the steppe population and later in Europe, probably driven by pathogenetic challenges coinciding with changes in diet, lifestyle and population density. This positive selection was because the MS and RA-associated variants under selection confer some resistance to a range of infectious diseases and pathogens. So quite interestingly, this study basically argued that from an evolutionary perspective, that positive selection took place positive genetic selection amongst the Yamnaya group for genetic variants that promote MS in a more prominent way, because these genetic variants basically protected them from different infectious diseases, because you're obviously major issues thousands of years ago. Now as we have seen, the ancestors of the Yamnaya people seem to predominantly be a group of hunter-gatherers that existed around the Dawn River region. But what else do we know about the Yamnaya people? To find out, please click here. Thanks for watching, please subscribe and hit the bell and tell your friends and family about this channel for ways to support them all be in the description below. 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