Second-oldest HIV-1 sequence identified
22 September 2008. Related: Basic science.
Richard Jefferys, TAG
A new study published in Nature reported the identification of the second-oldest known HIV-1 sequence. 
The sequence was recovered from a stored lymph tissue sample taken at a hospital in Kinshasa in 1960. The authors, led by Michael Worobey, were able to sequence around 5% of the HIV-1 genome and their analyses suggest that the virus began to spread and diversify in Africa around the turn of the century. The authors speculate that the growth of cities like Leopoldville facilitated an increase in transmission and the ultimate spread of HIV-1 across the globe.
Due to the many potential pitfalls associated with attempting to recover viral sequences from ancient samples, the work was confirmed by an independent laboratory, and the long lag time between the submission of the paper to Nature and publication also suggests that a great deal of rigor went into assuring the paper’s reviewers that the findings were accurate.
In a news article for Science, Jon Cohen provides some additional background, noting that the tissue sample came from a 28-year old woman and was part of a group of samples taken from individuals with illnesses that had defied diagnosis, including lymph node abnormalities. Many more such samples are available for study, and Michael Worobey hopes to continue shedding light on HIV-1’s early spread into the human population.
TAG Basic Science Blog (01 October 2008)
1. Worobey M et al. Direct evidence of extensive diversity of HIV-1 in Kinshasa by 1960. Letter. Nature 455, 661-664 (2 October 2008)
2. Cohen J. A viral blast from the past. Science Now Daily News (1 October 2008).