Dr Bunce was part of
the team that
analyzed the HIV
'fossil'.

Murdoch University's ancient DNA expert has been studying viral sequences that predate the discovery of the virus in the 1980s, providing valuable insights into the early spread and evolution of HIV-1, which evolves up to a million times faster than animal DNA.

Dr Michael Bunce, based at Murdoch University's Ancient DNA laboratory, had been part of the international research team that characterised RNA from an 'early' HIV-1 isolate from archival tissue samples taken from a woman in (what is now known as) Kinshasa, Democratic Republic of Congo, in 1960.

“The HIV-1 virus mutates so quickly that a sample from 1960 helps us to see how the virus has evolved and lets us improve estimates for when the original transmission from chimpanzees occurred,” Dr Bunce said.

The research paper, published 2 October in Nature (Vol 455), describes the analysis of viral sequences from a paraffin-embedded lymph node biopsy specimen, and its comparison against a viral sequence from 1959, the oldest known HIV-1 case and the only other pre-1976 HIV-1 viral sequence available to date.

“Finding an HIV-1 positive sample in amongst the 813 tissue blocks stored at Kinshasa University‟s pathology department is quite an achievement – it's akin to finding a needle in a haystack,” Dr Bunce said.

“Analysis of the 'fossil' virus with other HIV-1 sequences demonstrated that, by 50 years ago, group M HIV-1 strains had already undergone substantial diversification, and places the HIV-1's emergence at about 1908, when Léopoldville (now Kinsahasa) was emerging as a centre for trade.”

It's thought there could be many more paraffin-embedded HIV-1-infected specimens in the archival banks of west-central African hospitals, and that these could provide a vast source of clinical material for viral genetic analyses.

Resurrecting viral sequences from early African HIV-1 cases could offer insights into the evolution of the HIV/AIDS pandemic.