27 million ancestors and 100,000 years: this is the world’s largest family tree

Researchers at the University of Oxford in the UK have created the world’s largest family tree, with nearly 27 million ancestors over 100,000 years.

To carry out the study, scientists at the Big Data Institute in Oxford used thousands of genomic data from individuals, including prehistoric ones. The results were published in the journal Science.

Evolutionary geneticist Yan Wong, from the Big Data Institute, one of the authors of the study, said in a press release that it seeks to assemble a genealogy for all of humanity and tries to understand the history of genetic variation that we find in humans today.

“This genealogy allows us to see how each person’s genetic sequence relates to all others,” he says.

The research used DNA from eight different databases and included a total of 3,609 individual sequences from 215 populations. The oldest genes included samples found all over the world ranging from 1,000 to over 100,000 years ago.

To understand the combination of the set of trees, known as the “tree sequence” or “ancestral recombination plot,” the researchers needed to cross-reference current data with the genetic regions of the ancestors where the variation first appeared.

In the prototype, the algorithms are able to predict where common ancestors must be present in evolutionary trees to explain patterns of genetic variation.

Wong believes the study is laying the groundwork for the next generation of DNA sequencing.

“As the quality of genomic sequences from modern and ancient DNA samples improves, the trees will become even more accurate and we will eventually be able to generate a single, unified map that explains the descent of all the human genetic variation we see today,” he says. .

Family tree results

Studies of human fossils from the last decades have contributed to the study and storage of prehistoric data.

According to the results, the network contained about 27 million ancestors. The researchers also added location data on the genome samples to estimate where older generations lived.

The data showed some historical events in human evolution, such as migration out of Africa.

Now, the research team plans to make the map even more comprehensive, continuing to incorporate genetic data as it becomes available.

According to Anthony Wilder Wohns, who carried out the research as part of his doctorate at the Big Data Institute and is now a postdoctoral researcher at the Broad Institute of MIT and Harvard, the nine study reconstructs genomes from our ancestors and uses them to form a vast network of relationships.

“We can then estimate when and where these ancestors lived. The power of our approach is that it makes very few assumptions about the underlying data and can also include both modern and ancient DNA samples,” she says.

Still, he believes that the methodology can contribute to other areas of study, such as the evolution of all living beings, such as orangutans and bacteria.

“[A metodologia] may be beneficial for medical genetics, by separating the true associations between genetic regions and diseases from spurious connections arising from our shared ancestral history”, he concludes.