Scientists found that the oldest evidence of an HIV-related retrovirus called lentivirus date back to as early as 60 million years ago.
Lentiviruses are known to cause a variety of chronic diseases, ranging from the deadliest form of HIV/AIDS among humans and neurological disorders among primates.
The cure for HIV/AIDS has so far eluded scientists for decades, and this led researchers to study imprints left by related viruses in other animals to understand its origin.
However, scientists do not have enough knowledge about the history and origin of lentiviruses. Previous studies have traced the oldest known lentiviruses, which were found in lemurs, rabbits and ferrets, to 3 to 12 million years ago.
But a group of researchers from the Czech Academy of Sciences uncovered the oldest lentivirus ever identified, which was found to have emerged as early as 60 million years ago.
"We hope that our findings will allow virologists to better understand how lentiviruses evolved and how their hosts developed defenses against them," Daniel Elleder, lead researcher of the study, said in a press release.
The researchers used genomic data from the Malayan flying lemur (colugo) to trace the origins of lentiviruses. For the study, the researchers sequenced three samples of colugo genomic DNA that contain lentiviral remnants, followed by an analysis and reconstruction of ancient viral genomes.
The findings of the study were published in the advanced online edition of Molecular Biology and Evolution. According to the researchers, they plan to go deeper into the past by studying a broader spectrum of animals to learn more about the evolution of the lentrivirus.
Cases of HIV/AIDS are growing at an unprecedented rate. According to the Centers for Disease Control and Prevention (CDC), an estimated 44,073 people were diagnosed with HIV in the United States. To date, about 36.9 million people around the world are living with HIV.