Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers Find Ancient Roots for SIV

20.09.2010
The HIV-like virus that infects monkeys is thousands of years older than previously thought, according to a new study led by researchers from Tulane University.

Simian immunodeficiency virus (SIV), which is the ancestor to the human immunodeficiency virus (HIV), is between 32,000 and 75,000 years old and may even be more than a million years old, according to genetic analysis of unique SIV strains found in monkeys on Bioko, an island off the coast of Africa.

The research, which appears in the Sept. 17 issue of the journal Science, calls into question previous DNA sequencing data that estimated the virus’ age at only a few hundred years.

“The biology and geography of SIV is such that it goes from the Atlantic Ocean to the Indian Ocean all the way to the tip of Africa. It would take many, many thousands of years to spread that far and couldn’t have happened in a couple of hundred years,” said virologist Preston Marx of the Tulane National Primate Research Center who led the study in conjunction with Michael Worobey, evolutionary biologist at the University of Arizona.

Marx tested his theory that SIV had ancient origins by seeking out DNA samples from monkey populations that had been isolated for thousands of years. His team collected bush meat samples from monkeys on Bioko, a former peninsula that separated from mainland Africa after the Ice Age more than 10,000 years ago.

Researchers found four different strains of SIV that were highly genetically divergent from those found on the mainland. They compared DNA sequences of the viruses with the assumption that they were tracking how both evolved over 10,000 years. The computer modeling showed the rate of mutation to be much slower than previously thought, indicating that virus is between 32,000 and 75,000 years old to have evolved to its current state. These dates set a new minimum age for SIV, although it is likely to be even older, Marx says.

The research has implications for HIV. Simian immunodeficiency virus, unlike HIV, does not cause AIDS in most of its primate hosts. If it took thousands of years for SIV to evolve into a primarily non-lethal state, it would likely take a very long time for HIV to naturally follow the same trajectory, Marx says.

The study also raises a question about the origin of HIV. If humans have been exposed to SIV-infected monkeys for thousands of years, why did the HIV epidemic only begin in the 20th century?

“Something happened in the 20th century to change this relatively benign monkey virus into something that was much more potent and could start the epidemic. We don’t know what that flashpoint was, but there had to be one,” Marx says.

Reporters can request a copy of the full article from the Science Press Package Office at scipak@aaas.org. Other Tulane co-authors of the study include Meredith Hunter, lab manager at Tulane National Primate Research Center, Clint Coleman, post-doctoral fellow at the Tulane Cancer Center, and researchers Paul Telfer, Michael J. Metzger and Patricia Reed.

Keith Brannon | Newswise Science News
Further information:
http://tulane.edu/news/

Further reports about: Africa Ancient African Exodus DNA DNA sequence HIV Pacific Ocean SIV Science TV

More articles from Life Sciences:

nachricht Water world
20.11.2017 | Washington University in St. Louis

nachricht Carefully crafted light pulses control neuron activity
20.11.2017 | University of Illinois at Urbana-Champaign

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Antarctic landscape insights keep ice loss forecasts on the radar

20.11.2017 | Earth Sciences

Filling the gap: High-latitude volcanic eruptions also have global impact

20.11.2017 | Earth Sciences

Water world

20.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>