Groundbreaking new scientific findings have changed researchers' understanding of the origins of the HIV virus. A genetic study has revealed that cousins of the virus, originally thought to have existed for just tens of thousands of years, actually developed in primates millions of years ago.

Researchers have long known that HIV-like viruses, called lentiviruses, existed in primates for millennia before they jumped from chimps to people in the 20th century. But while examining genetic signatures of these viruses in African primates, scientists spotted lentivirus-spurred changes in the animals' immune systems that evolved over a period of 5 million to 16 million years.

The finding could shed light on how man's closest relatives evolved to fight the viruses, and what we can do to develop HIV immunity now. "This kind of research helps us understand how the virus works," says Dr. Sam Wilson of the MRC — University of Glasgow Centre for Virus Research. "The hope is that one day this will translate into therapy."

In the meantime, Australian scientists have developed a form of gene therapy they say causes the HIV virus to self-destruct by changing how it replicates in the human body. They plan to start testing the treatment on mice this year, but getting FDA approval for treatment on humans could take as long as 10 years.