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 firstname.lastname@example.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
Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH
Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences