Albert Perry was born into slavery in South Carolina sometime around 1820. In 2012, one of his great-grandsons took a Y-DNA test, which led to the discovery of the most divergent Y-DNA lineage known today, haplogroup A00. This lineage would later be traced to Cameroon.
The Perry family in the USA and the distant cousins in Cameroon all descend from a single ancestor who lived just over 1,000 years ago, but they are the most distant paternal line relatives of almost everyone in the world today.
Albert’s son, Clyde Perry, born in 1867, grandfather of the first A00 tester.
To find where Perry’s Y chromosome may have come from, samples from around Africa were tested. Several more from Perry’s branch were found amongst the Mbo people of Cameroon.
Geneticists can use such samples to work out how we are related to one another. Hundreds of thousands of people have now had their DNA tested. The data from these tests had shown that all men gained their Y chromosome from a common male ancestor. This genetic “Adam” lived between 60,000 and 140,000 years ago.
All men except Perry, that is. When Family Tree DNA’s technicians tried to place Perry on the Y-chromosome family tree, they just couldn’t. His Y chromosome was like no other so far analysed.
“The Y-chromosome tree is much older than we thought,” says Chris Tyler-Smith at the Wellcome Trust Sanger Institute in Hinxton, UK, who was not involved in the study. He says further work will be needed to confirm exactly how much older.
“It’s a cool discovery,” says Jon Wilkins of the Ronin Institute in Montclair, New Jersey. “We geneticists have been looking at Y chromosomes about as long as we’ve been looking at anything. Changing where the root of the Y-chromosome tree is at this point is extremely surprising.”
https://www.newscientist.com/article/dn23240-the-father-of-all-men-is-340000-years-old/
This Adam was not the first man, or the only man, from his time to contribute to modern human DNA. It is just that, by chance, his Y chromosome was the only one to survive until today.
So can this tell us anything about human origins? Central Africa contains Y chromosomes from both Perry’s branch and the former-Adam’s branch, while the rest of the world has only been shown to contain the former-Adam’s branch (with the exception of Perry himself). This suggests that our revised Adam may have lived in Central Africa.
The oldest-known “modern human” bones are from East Africa. But if Adam lived in Central Africa, does that mean that modern humans could have originated there? Again, it is hard to say. By looking further into the genetics of modern people, the picture becomes even more complex.
Given the scarcity of Perry’s branch and the lack of diversity within it, it is also possible that the revised Adam could have been an ancestor of two sub-species (or even species). Could one have become modern humans, while another produced a cousin? What if, long after modern humans had become established and started to spread, they should meet and interbreed? Like all our other close relatives, these cousins eventually disappeared, but maybe they left traces, such as Perry’s Y chromosome, in the modern gene pool.
https://theconversation.com/albert-and-adam-rewrite-the-story-of-human-origins-15835
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4135414/
The Perry family in the USA and the distant cousins in Cameroon all descend from a single ancestor who lived just over 1,000 years ago, but they are the most distant paternal line relatives of almost everyone in the world today.
Albert’s son, Clyde Perry, born in 1867, grandfather of the first A00 tester.
To find where Perry’s Y chromosome may have come from, samples from around Africa were tested. Several more from Perry’s branch were found amongst the Mbo people of Cameroon.
Geneticists can use such samples to work out how we are related to one another. Hundreds of thousands of people have now had their DNA tested. The data from these tests had shown that all men gained their Y chromosome from a common male ancestor. This genetic “Adam” lived between 60,000 and 140,000 years ago.
All men except Perry, that is. When Family Tree DNA’s technicians tried to place Perry on the Y-chromosome family tree, they just couldn’t. His Y chromosome was like no other so far analysed.
Deeper roots
Michael Hammer, a geneticist at the University of Arizona in Tucson, heard about Perry’s unusual Y chromosome and did some further testing. His team’s research revealed something extraordinary: Perry did not descend from the genetic Adam. In fact, his Y chromosome was so distinct that his male lineage probably separated from all others about 338,000 years ago.“The Y-chromosome tree is much older than we thought,” says Chris Tyler-Smith at the Wellcome Trust Sanger Institute in Hinxton, UK, who was not involved in the study. He says further work will be needed to confirm exactly how much older.
“It’s a cool discovery,” says Jon Wilkins of the Ronin Institute in Montclair, New Jersey. “We geneticists have been looking at Y chromosomes about as long as we’ve been looking at anything. Changing where the root of the Y-chromosome tree is at this point is extremely surprising.”
https://www.newscientist.com/article/dn23240-the-father-of-all-men-is-340000-years-old/
This Adam was not the first man, or the only man, from his time to contribute to modern human DNA. It is just that, by chance, his Y chromosome was the only one to survive until today.
So can this tell us anything about human origins? Central Africa contains Y chromosomes from both Perry’s branch and the former-Adam’s branch, while the rest of the world has only been shown to contain the former-Adam’s branch (with the exception of Perry himself). This suggests that our revised Adam may have lived in Central Africa.
The oldest-known “modern human” bones are from East Africa. But if Adam lived in Central Africa, does that mean that modern humans could have originated there? Again, it is hard to say. By looking further into the genetics of modern people, the picture becomes even more complex.
Given the scarcity of Perry’s branch and the lack of diversity within it, it is also possible that the revised Adam could have been an ancestor of two sub-species (or even species). Could one have become modern humans, while another produced a cousin? What if, long after modern humans had become established and started to spread, they should meet and interbreed? Like all our other close relatives, these cousins eventually disappeared, but maybe they left traces, such as Perry’s Y chromosome, in the modern gene pool.
https://theconversation.com/albert-and-adam-rewrite-the-story-of-human-origins-15835
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4135414/
