HIV - Out of Africa, via Haiti

The origin of HIV in North America has been a hotly contested issue. It's had conspiracy theories (the Nazi's invented it, it was designed by a pharmaceutical company to kill off Africans), African origin theories, biblical theories (Gods punishing homosexuals) and many many others.

Well, it seems we're a significant step closer to actually telling where the heck HIV did come from.

HIV was first formally described around the 1980's, but it was believed that the first cases (Robert R, famously... a possible African-American rent-boy from LA) were around the 1968 mark.

Well, the news is now out. It seems that it was no coincidence that initial 'outbreak' in the USA was among Haitians. Using new mutation analysis techniques, a group from the University of Arizona in Tucson has now identified the path of the virus by analysing a number of old stored samples from that initial outbreak. The current new hypothesis is that the jump from simians to humans occurred around the 1930's, making the 'big' jump from Haiti to the USA around 1969 (give or take a year, apparently). Their paper has a neat little diagram showing where the virus went, how the virus has spread. Infact, their consensus data is pretty convincing, and seems like they have definitively nailed this little link down.

The final implication of all of this is that HIV must have been floating about in the USA for about 10 years before anyone actually clued up that something was up. Furthermore, there is plenty of evidence that there were several good cases in the mainland USA (Los Angeles, Detroit, Chicago, New York etc) for some time before the first case was identified.

What else could we be incubating?

Lights Out For Merck's HIV Vaccine Program?

Perhaps underscoring ARW's suggestion re the need to explore alternative approaches to dealing with infectious disease, Merck have ended their phase II HIV vaccine trial due to lack of efficacy. This spells the end for their Adenovirus-based vector, the fruits of 20 years of R & D work. At least for the time being, they apparently have no specific plans to continue their HIV vaccine program.

Maybe a vector that induces a more vigorous immune response, such as VSV or vaccinia, will be more successful...and maybe Merck or competitors will be shopping around for new vector platforms in the near future...

Science blogger gets sued: for once it's not me!

PZ Myers, over at the pharyngula blog, is getting sued for libel to the tune of $15M by Stuart Pivar. The story is eerily familiar, Pivar is a businessman who thinks geneticists have it all wrong and has his own version of evolution and developmental biology. He decided to write a book about it called Lifecode, which he sent for review to PZ Myers. Myers being a developmental and evolutionary biologist called the book for what it is, bullshit, exposed all of the factual scientific errors and called Pivar a "crackpot". Now Pivar's feelings are hurt and he is suing, and he has the money to do so. I don't know yet if the World Court is involved.

Speaking of crackpots, PLOS has a good article exposing some of the HIV deniers, including our favorite character Duesberg:

"Interestingly, alternative hypotheses for AIDS causation depend on where the patient lives. In Africa, HIV deniers attribute AIDS to a combination of malnutrition and poor sanitation, i.e., they believe that AIDS is simply a relabeling of old diseases. In America and other wealthy countries, they claim AIDS is caused by drug use and promiscuity. Duesberg has long been an advocate of the idea that the use of “poppers,” or amyl nitrate, is a cause of AIDS in the gay community [31]. With the identification of AIDS in individuals who have never used poppers, this hypothesis has been widened by HIV deniers to implicate a number of recreational drugs (cocaine, crack, heroin, methamphetamines) as well as prescription drugs such as antibiotics and steroids in the etiology of AIDS. HIV deniers have criticized the idea that immunosuppression due to infection with HIV could result in all of the different infections that characterize AIDS, and yet they support the idea that poppers or other drugs—including many that have not been shown to cause severe immune deficiencies—could cause AIDS. In the past decade, the very drugs used to treat HIV/AIDS have come under fire by HIV deniers, who have suggested that the medicines themselves are a cause of AIDS"

You know I've never figured out why pharyngula is so popular, it's always the same creationist bashing, with a picture of a cephalopod thrown in from time to time. I mean I dislike creationists as much as the next scientist, but man it gets old quickly, the bayblab is soo much better.

Splicing out integrated HIV

Those of us doing mouse work are probably already familiar with the CRE-lox system, which uses a recombinase called CRE to excise fragments of DNA in the genome that are flanked by loxP sites (floxed in the lingo). This technique is mostly used for conditional transgenic to gain tissue-specific Ko for example, which is the bane of my existence.

Well some clever folks in Germany decided to evolve the CRE enzyme in vitro to recognise the viral LTR flanking sites of HIV instead of loxP. The results are quite encouraging:

"HIV-1 integrates into the host chromosome and persists as a provirus flanked by long terminal repeats (LTRs). To date, treatment regimens primarily target the virus enzymes or virus-cell fusion, but not the integrated provirus. We report here the substrate-linked protein evolution of a tailored recombinase that recognizes an asymmetric sequence within an HIV-1 LTR. This evolved recombinase efficiently excised integrated HIV proviral DNA from the genome of infected cells. Although a long way from use in the clinic, we speculate that this type of technology might be adapted in future antiretroviral therapies, among other possible uses."