A nearly - complete HIV genome sequence has been found in one of 1,600 tissue samples collected in Kinshasa , Democratic Republic of Congo , in the sixties . Dating from 1966 , the genome is 10 yr onetime than any like discovery . Although older HIV succession havebeen find out , these were all short fragments with much less information to offer up about HIV ’s blood line . The discovery has allowed scientists to essay theory on the timing of HIV ’s appearance and the hurrying with which it mutates .
Although the world did not become aware of AIDS until the 1980s , and the oldest confirmed cases date from a decade before , there is plenty of grounds the virus is much older . Judging by the accretion of variation in different viral strains , virologists have guess the shift from simian immunodeficiency virus ( SIV ) to HIV come between 1881 and 1920 . Inconsistencies in estimation of the rate SIV evolves have led some to wonder these date , however . get old HIV sequences and compare them with mod ones is the most likely fashion to decide these argumentation .
The question of HIV ’s origins has taken on new import now the world faces a new computer virus that also crossed from non - human animals . The more we cognise about how deathly diseases jump the species roadblock , the well our chances of preventing them in future . KU Leuven University’sDr Sophie Gryseelsis part of a squad that has produce a new method , jazz as the air hammer RT - PCR , particularly suited to observe viral genome sequence in sure-enough samples . They claim to have found eight of the oldest nine HIV-1 sequences situate so far .
The earliest of these was from 1976 , but Gryseels and co - source describe inProceedings of the National Academy of Sciencesfinding the virus in a sample distribution taken in 1966 from a man who was 38 at the time . Nothing is known about his subsequent life . A equivalence of the sequence with version collect today “ provides unmediated evidence that HIV-1 molecular clock estimates span the last half - century are remarkably reliable , ” the report concludes .
The computer virus is from HIV-1 radical M , which accounts for more than 98 percent of casing .
Finding older sequences is important , the author argue , because “ pace of molecular evolution look to diverge depending on the time chassis considered , so rate forecast over a late meter frame can not necessarily be extrapolate [ further back ] . ”
inescapably , cabal possibility about the origins of HIV are democratic , include that it came from aninfected muckle of polio vaccinesor was deliberately make as a bioweapon . All these trust , however , on HIV having first appeared relatively recently . Evidence date it to at least the 1920s , like this uncovering , refutes such title .
That does n’t mean HIV ’s appearance was random , however . There are good reasons to conceive displacement triggered by settlement expanded the bushmeat trade , exposing hunters to SIV , just as SARS - CoV-2 may ensue from human intrusion on animal habitat .
