Feeds

DNA reveals human-chimp crossbreeding

Romeo and Ju-oo-oo-oo-liet

Beginner's guide to SSL certificates

A new study of chimpanzee and human genomes has revealed that the two lineages leading to the modern species interbred after they split. According to the report to be published in Nature today, the story of how we left our hirsute cousins behind is more complicated than previously thought.

Researchers at MIT's Broad Institute used powerful statistical techniques to fit our DNA sequences against chimps', giving some surprising results.

Senior author David Reich explained: “The study gave unexpected results about how we separated from our closest relatives. Something very unusual happened at the time of speciation.”

Investigations of the X chromosome revealed it's around 1.2m years “younger” than the rest of the genome. Co-author Eric Lander said: “The young age of chromosome X is an evolutionary smoking gun.”

Because the X chromosome is one of the two sex chromosomes, controlling traits important to breeding, selection acts most strongly to change it after hybridisation.

This is interpreted to mean after the apes that would evolve into chimps and humans first separated, two got it together and mixed things up again. The star-crossed pair's kid became our ancestor.

The timing of the initial separation was later than expected too. Fossil evidence had put the split at between 6.5m and 7.4m years ago, but the new genetic comparison brings the event forward probably less than 5.4m years ago. Past genetic studies had shown that different regions of the genome diverged at different times, but the new work is the first to put dates on the splits.

Lead author Nick Patterson said: “If the dating is correct, the fossil would precede the human-chimp split. The fact that it has human-like features suggest that human-chimp speciation may have occurred over a long period with episodes of hybridisation.”

The team say that their discovery could mean that the way animal species form has to be reconsidered. Reich said: "That [hybridisation] events have not been seen more often may simply mean that we have not been looking for them."

The plan now is to butress these important findings with DNA from gorillas and other primates.®

Remote control for virtualized desktops

More from The Register

next story
Bond villains lament as Wicked Lasers withdraw death ray
Want to arm that shark? Better get in there quick
Antarctic ice THICKER than first feared – penguin-bot boffins
Robo-sub scans freezing waters, rocks warming models
Your PHONE is slowly KILLING YOU
Doctors find new Digitillnesses - 'text neck' and 'telepressure'
SEX BEAST SEALS may be egging each other on to ATTACK PENGUINS
Boffin: 'I think the behaviour is increasing in frequency'
Reuse the Force, Luke: SpaceX's Elon Musk reveals X-WING designs
And a floating carrier for recyclable rockets
The next big thing in medical science: POO TRANSPLANTS
Your brother's gonna die, kid, unless we can give him your, well ...
NASA launches new climate model at SC14
75 days of supercomputing later ...
Renewable energy 'simply WON'T WORK': Top Google engineers
Windmills, solar, tidal - all a 'false hope', say Stanford PhDs
Britain's HUMAN DNA-strewing Moon mission rakes in £200k
3 days, and Kickstarter moves lander 37% nearer takeoff
prev story

Whitepapers

Why and how to choose the right cloud vendor
The benefits of cloud-based storage in your processes. Eliminate onsite, disk-based backup and archiving in favor of cloud-based data protection.
Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Driving business with continuous operational intelligence
Introducing an innovative approach offered by ExtraHop for producing continuous operational intelligence.
10 threats to successful enterprise endpoint backup
10 threats to a successful backup including issues with BYOD, slow backups and ineffective security.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?