HIV's ancestors 'plagued first mammals'

September 18, 2009
HIV's ancestors 'plagued first mammals'
The remains of an ancient HIV-like virus have been discovered in the genome of the two-toed sloth.

(PhysOrg.com) -- The retroviruses which gave rise to HIV have been battling it out with mammal immune systems since mammals first evolved around 100 million years ago - about 85 million years earlier than previously thought, scientists now believe.

The remains of an ancient HIV-like virus have been discovered in the genome of the two-toed sloth [Choloepus hoffmanni] by a team led by Oxford University scientists who publish a report of their research in this week’s Science.

'Finding the fossilised remains of such a virus in this sloth is an amazing stroke of luck,’ said Dr Aris Katzourakis from Oxford’s Department of Zoology and the Institute for Emergent Infections, James Martin 21st Century School. ‘Because this sloth is so geographically and genetically isolated its genome gives us a window into the ancient past of mammals, their immune systems, and the types of viruses they had to contend with.’

The researchers found evidence of ‘foamy viruses’, a particular kind of retrovirus that resembles the complex lentiviruses, such as and simian retroviruses (SIVs) - as opposed to simple retroviruses that are found throughout the genomic record.

‘In previous work we had found evidence for similar viruses in the genomes of rabbits and lemurs but this new research suggests that the ancestors of complex retroviruses, such as HIV, may have been with us from the very beginnings of mammal evolution,’ said Dr Aris Katzourakis.

Understanding the historical conflict between complex viruses and mammal immune systems could lead to new approaches to combating existing retroviruses, such as HIV. It can also help scientists to decide which viruses that cross species are likely to cause dangerous pandemics - such as swine flu (H1N1) - and which, like (H5N1) and foamy viruses, cross this species barrier but then never cause pandemics in new mammal populations.

Provided by Oxford University (news : web)

Explore further: Rabbits hold key to HIV-like virus

Related Stories

Rabbits hold key to HIV-like virus

March 23, 2007

The remains of an ancient HIV-like virus have been found in rabbits. Scientists at Oxford University discovered the unique lentivirus, part of a family of viruses closely related to HIV, ‘fossilised’ inside the genome ...

Recommended for you

Amateur paleontologist finds rare fossil of fish in Arizona

September 3, 2015

Growing up, Stephanie Leco often would dig in her backyard and imagine finding fossils of a tyrannosaurus rex. She was fascinated with the idea of holding something in her hand that was millions of years old and would give ...

X-rays reveal fossil secrets

September 3, 2015

A sophisticated imaging technique has allowed scientists to virtually peer inside a 10-million-year-old sea urchin, uncovering a treasure trove of hidden fossils.

Early human diet explains our eating habits

August 31, 2015

Much attention is being given to what people ate in the distant past as a guide to what we should eat today. Advocates of the claimed palaeodiet recommend that we should avoid carbohydrates and load our plates with red meat ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.