In a breakthrough that may lead to the invention of a new AIDS drug, American scientists have identified an HIV genetic stowaway that helps the deadly virus transmit and replicate in people.

The researchers from the University of Rochester Medical Center, New York, have found the previously unnoticed stretch of genetic material in the RNA sequence of the virus that may have come from a related cat virus. HIV is a ‘retrovirus’ which uses RNA in place of DNA to function, journal Nature Structural and Molecular Biology reported.

“We not only found the gene, but also a plausible explanation for why it is still there after millions of generations: its presence makes HIV dramatically better at reproducing inside of our cells,” lead author Dr. Robert Bambara said.

The discovery can pave way for designing new drugs or a vaccine against the deadly HIV virus and it may also reveal information about how other viruses like swine flu transmit from animals to people.

“This suggests new ways to shut down with drugs the ability of the virus to mass produce copies of itself,” the researchers said.

It is believed that HIV virus was transmitted to humans from chimpanzees infected with the deadly virus’s close relative called simian immunodeficiency virus or SIV.

Feline immunodeficiency virus (FIV), which infects cats, is thought to be the virus from which SIV originated and therefore it is an ancestor of HIV,” the researchers said.

They said, “HIV-related viruses have been identified in sheep, goats, horse, cattle and cats, but only the cat virus FIV seems to be a close relative of HIV and SIV.”

The scientists added that the gene is very much similar to human tRNALys that HIV needs to replicate itself. “Like all viruses, HIV lives by infecting cells, usurping their machinery and changing them into manufacturing units that make copies of the virus.

“Determination of the origin of the tRNA-like sequence should provide valuable clues about the ancestry of HIV,” the researchers pointed out.

As per UN figure, presently the number of people infected with the HIV is an estimated 33.4 million and the deadly virus has already killed 25 million.

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