We do not want to alarm you, but your mutations are not what they were a million years ago. Sorry
By comparing genetic changes in the offspring of various primates, researchers have determined the mutation rate of humans has slowed since we have parted ways. X-Men franchise fans might be disappointed, but the results could clear some questions about our past
We have been fascinated with our own genetic material for as long as we have been able to study it, and have done a pretty thorough job of not only mapping our genes, but working out the rates at which they change.
"Over the past six years, several large studies have done this for humans, so we have extensive knowledge of the number of new mutations that occur in humans every year," says geneticist Søren Besenbacher from Aarhus University. "Until now, however, there have been no good estimates of mutation rates in our closest primate relatives."
Researchers from Aarhus University and Copenhagen Zoo collected genetic information from parents and offspring of chimpanzees, gorillas, and orangutans to compare their mutation rates with their own
An analysis of their DNA sequences revealed the number of new mutations that appeared in each generation, allowing the team to compare figures across various branches of primate fa mily tree.
In comparison with similar data collected on humans, and the relative differences in the age of the parents, the mutation rate in each of the 1
The results also suggest that this slowdown began relatively recently in our history, perhaps as little as 400,000 years ago, not long before our ancestors qualified as modern humans
This change has some pretty significant consequences when it comes to using our
Like the ticking of a metronome, we can use the 'beats per minute' of mutating DNA to figure out when two related species were the last members of the same band. ] If we go by the modern human beat, the last ancestor we had in common with our closest cousin, the chimpanzee, existed about 10 million years ago. Indeed, one study pinpoints our division at around 13 million years in the past.
Other genetic measures, however, could suggest a split closer to 4 million years.
The new results could help clarify this discrepancy, leaning towards a separation of about 6 to 7 million years. 19659002] "The times of speculation we can now calculate on the basis of the new rate fit in much better with the speciation times we would expect from the fossils of human ancestors that we know of," says senior researcher Mikkel Heide Schierup from Aarhus University.
It could also prompt us to rethink the divergence of Neanderthal and modern human ancestors, requiring us to recalculate estimates based on a slightly higher rate of mutation than we currently do
Just what could have caused this slowdown is anybody's guess. The researchers speculate it could have something to do with our late-onset puberty and longer generation spans.
It is unlikely to have affected the rate at which our genes spread and to help us adapt – our evolution has been barrelling along at break neck speeds. adaptation could do more than help us understand our own history.
"All species of great apes are endangered in the wild," says Copenhagen Zoo's Christina Hvils.
"With more accurate dating of how populations have changed in relation to climate over time, we can get a picture of how species could cope with future climate change. "
This study was published in Nature Ecology & Evolution .