DNA
sequences can reveal information about an organism that no other fossil or artifacts can tell us. Specifically for humans, the genetic sequences from
existing populations have revealed how those population have migrated and bred
with the native populations. Even then it would always be more exciting if we
could find what the genetic makeup of our ancestors was. For us it would be as
close as we could in meeting them in person. We could know who they were, what
special properties they had that we might have inherited, possible diseases
they carried, etc. And more importantly, like we all always wonder ... from
where have we come from.
Taken from the original paper (https://www.nature.com/articles/s41586-023-06035-2)
I would
personally want to know how and where my ancestors 10, 100 or 500 generations
from now have lived. Had they been living near my hometown since thousands of
years? Or have they migrated from a faraway place crossing several valleys and
mountains?
Some
scientists from Germany and The Netherlands have just opened a way to know
about our ancestors from the things that they have left behind. They have
developed a way to extract the DNA of the person wearing some artifacts.
Artifacts like the jewelry they ear; in this case a pendant made of deer tooth.
Bones and teeth are porous and also tend to absorb bodily fluids. The bodily
fluids such as sweat contains the DNA of the person. Therefore, when a person
wears jewelry made of bones and teeth some, the sweat of the person can be
absorbed by the jewelry. In addition to being porous, bones and teeth also
contain hydroxyapatite which adsorbs DNA and protects it from degradation. DNA
trapped here can potentially last for thousands of year. This brings us back to
what these scientists have achieved in the paper
published in Nature, which was graciously made publicly available.
The
researchers essentially developed a method by which we can extract DNA from
ancient bones. In summary, the method consists of soaking the material in
phosphate buffer and detergent at different temperatures. To read about the
original paper in which they describe this method, you can click here.
In the
latest study, they scientists used six artifacts of similar size and tried to
see what DNA they could extract from them. From, one of the artifacts, a
pendant made from deer tooth, they were able extract human DNA. As simple as it
may sound but it consists of several intricate steps such as library
preparation, enrichment and sequencing and requires a lot of hard work.
After
analysis of the DNA sequence and from the location where the tooth pendant was
found, the probable wearer of the pendant was a female who lived around 18.5
thousand years ago near Denisova cave which now is in Siberia, Russia.
Interesting the closest existing relative to the woman are Native Americans.
The DNA sequenced matched more closely to an older population of humans (now
termed as Ancient North Eurasians) that were living around the same time
further east in Siberia. It also gives an insight how humans had migrated
toward the American continent via the Siberia.
Comments
Post a Comment