Researchers confirmed that two of the four known groups of human AIDS viruses originated in western lowland gorillas.
HIV-1, the virus that causes AIDS, is believed to have been spread from animals to humans on four separate occasions, leading to the virus lineages groups M, N, O, and P, Perelman School of Medicine at the University of Pennsylvania reported. Past research has linked groups M and N to geographically distinct chimpanzee communities in southern Cameroon, but the origins of groups O and P have been largely uncertain.
"Understanding emerging disease origins is critical to gauge future human infection risks," said Martine Peeters from Montpellier. "From this study and others that our team has conducted in the past it has become clear that both chimpanzees and gorillas harbor viruses that are capable of crossing the species barrier to humans and have the potential to cause major disease outbreaks."
Group M is believed to have been linked to the AIDS pandemic that infected over 40 million people across the globe. Groups N and P have only been found in a select few individuals and has remained isolated to Cameroon, while group O infected more than 100,000 people in west central Africa.
To make their findings the researchers looked at fecal samples from "western lowland gorillas, eastern lowland gorillas, and mountain gorillas in Cameroon, Gabon, the Democratic Republic of Congo, and Uganda" for signs of primate SIVgor infection. The study allowed them to pinpoint four sites in southern Cameroon in which local western lowland gorillas carry SIVgor.
"Viral sequencing revealed a high degree of genetic diversity among the different gorilla samples," said Beatrice Hahn, a professor of Medicine and Microbiology,. "Two of the gorilla virus lineages were particularly closely related to HIV-1 groups O and P. This told us that these two groups originated in western lowland gorillas."
The findings were published in a recent edition of the Proceedings of the National Academy of Sciences.
