Example chart showing the evolution of mtDNA Haplogroups to MRCA. Image credit: C. Rottensteiner

A new study provides evidence that appears to confirm a genetic Adam and Eve. As almost every man and woman on Earth can trace their origins back to these two peoples of the prehistoric world.

The genetic Adam and Eve also appear to be far older than previously thought, and what is perhaps most startling is the fact that they didn’t even live near each other.

The study Genetic Adam and Eve did not live too far apart in time was published in the journal Science last week (also Nature) and it outlines genetic research that enables researchers to date these two genetic ancestors to about 135,000 years ago. Making them far older than the previously thought 50,000 to 60,000 years ago.

The dating was made possible by tracking and analyzing the male chromosome, the Y-chromosome, and mitochondrial DNA. Since the Y-chromosome is passed down identically from father to son, small mutations over time can be traced back the male line to a time when we were a lot fewer on Earth, to an ancient “father of all humans” if you like. And the mitochondrial DNA, the “power plants” of the cells, is carried inside the egg, with only women passing it on to their children. This DNA can reveal the maternal lineage to an ancient Eve, a “mother of all humans”.

The researchers sequenced the entire genome of the Y chromosome for 69 men from seven global populations, from Africa to Siberia. The team then analyzed this data to conclude that all 69 males shared a single male ancestor in Africa roughly 125,000 to 156,000 years ago. They did the same with the mitochondrial DNA using samples from 24 women, concluding that all woman can trace their lineage back to an “Eve” who lived in Africa between 99,000 and 148,000 years ago. However, this man and woman are just two among thousands of people who were alive at this time in history with unbroken lineages to today.

Mitochondrial DNA with electron microscopy. Credit: Francisco J Iborra1 , Hiroshi Kimura2 and Peter R Cook.

Other studies have dated the ancient male and woman ancestors to similar timelines, one study showed that many African males have a unique Y-chromosome that they can trace back to a man who lived between 237,000 and 581,000 years ago.

As a follow-up study, the team of geneticists at Stanford University in California will now sequence the Y chromosomes from nearly 2,000 men. With the hope that this broader genetic source will provide the researchers with enough data to more precisely pinpoint the time and area to where these ancient ancestors lived.

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Genetic Adam and Eve did not live too far apart in time
Common genetic ancestors lived during roughly same time period, scientists find
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