German and American scientists have developed a new powerful tool for studying ancient DNA, which allows with unprecedented accuracy to identify both close and distant relatives in the genomes of people who lived hundreds and thousands of years ago. A study published in the journal Nature Genetics was conducted by specialists from the Max Planck’s Evolutionary Anthropology Institute in Leipzig and Harvard University.
The method is based on the analysis of DNA segments called IBD (Identity by Descent), which are almost identical to relatives and inherited from the common ancestor. Until now, such segments have been studied only in modern DNA, but the new Ancibd tool allows them to be extracted from ancient genomes.
The main difficulty was that ancient DNA is often very degraded. Scientists have found an innovative way of filling spaces in ancient genomes using modern reference DNA panels.
By applying a new tool to a database of 4,248 ancient genomes, scientists identified hundreds of previously unexplained parliaments of relatives. In some cases, relatives were buried at a great distance from each other, which shed light on the mobility of the ancient peoples. For example, a couple of relatives from the early Bronze Age were discovered, who lived about 5,000 years ago and had a fifth degree of kinship. They were buried at a distance of about 1,500 kilometers from each other.
In addition, the new method allowed scientists to explore even more distant relatives. They were able to identify previously unknown connections between ancient cultures, demonstrating close relations between them. In some cases, great distances were overcome in just a few hundred years.
This new method of analyzing ancient DNA provides researchers with a powerful computing tool. Given the fact that the area of study of ancient DNA is developing rapidly, and every year thousands of ancient genomes are produced, this new tool will help scientists better understand the life of our ancestors both at the micro level and on the scale of large cultural and historical events.