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Scientists Expose Weak DNA in HIV
Ace905 writes "The National Institute of Allergy and Infectious Diseases announced Thursday that they had discovered a very promising 'weak spot' in the HIV virus. The HIV virus, a progenitor to full blown AIDS has eluded all attempts at a vaccine since it was discovered sometime in the 1970's. The major problem with developing a vaccine initially was isolating the virus. Conventional viruses are often defeated with existing drugs, or after being tested against new compounds. HIV has been unique, and staggering in it's ability to resist all attempts at treatment by mutating its own genetic code. HIV is able to resist, with great effectiveness, any drug or combination drug-therapy that is used against it."
This is about finding a stable surface protein on the surface of HIV which may be a good target for the production of an antigen which would elicit a stable immune response as a number of people have antibodies which target the same site. This has nothing to do with DNA, the submitter is just biologically illiterate.
The article summary needs further assistance. AIDS was identified in 1981.
If you mod me down, I shall become more powerful than you could possibly imagine.
It is highly improbable that the mutation rate in that part of the genome is lower. The b12 epitope overlaps with part of the CD4 binding site (the point of the Nature article referenced by the BBC report), it is thought to be functionally important for engaging the receptor, mutations in the region are therefore selected against. It is a weak spot in HIV's defense against the host, but not 'weak DNA' which suggests, at least to me, that the DNA is somehow brittle. At any rate, the weak spot is the accessibility of the gp120 epitope to neutralizing antibodies, and that is the weakness that people want to exploit.
From the article:
They have published an atomic-level image in Nature showing the antibody, b12, attacking part of a protein on surface of the virus.
So, yes it has been published - and Nature is a top-tier journal.
Reading code is like reading the dictionary - you have to read half of it before you can go back and understand it.
b12 is a family of human antibodies that targets this viral protein gp120. gp120 is therefore the candidate for the vaccine. For vaccines we usually just inject viral protein(s) - as we would in this case - or a weak or dead form of the virus, and let the body make the antibodies (the b12 family in this case).
The talk about 'region' in this article probably refers to a site on the RNA of the virus: this region, encoding protein gp120, is not much changed by mutations - HIV codes genes in RNA since it's a retrovirus.
Also, since HIV targets the immune system, when someone has AIDS - the later stages of the disease in which the immune system is broken (targeted by HIV are T-cells) - vaccination may no longer work, since the immune system is no longer capable of producing antibodies, unless the T-cell count can be brought back to a level in which antibodies can be made.
HIV is a retrovirus so any weak spots would be found in the RNA, not the nonexistent DNA. Interestingly, the BBC decided to sidestep this issue by not mentioning any nucleic acids at all.
What do you mean 'HIV has never been seen...'? That's just not true
Ye have made your way from the worm to man, and much within you is still worm.
Also, HIV is a retrovirus. For this family of viruses, their genome spends the majority of its time, and especially as an infectious particle, as RNA. It is only after infraction does its genome get replicated into DNA (through a process known as reverse transcription using a virally encoding RNA dependent DNA polymerase known as reverse transcriptase.) After being copied into DNA, the pro-virus is then inserted into the host's genome where RNA molecules are made (transcribed) to make viral proteins and full length copies of its genome for packaging into new infectious viral particles. This is a very import aspect of the virus' life-cycle and has many implications for some of the anti-retroviral therapies on the market.
More specifically, HIV is a retrovirus. This means that as a standalone virus it contains RNA, but when it enters a cell, it uses reverse transcriptase to transcribe its RNA sequence into the equivalent DNA strand, which the cell's normal transcription/translation mechanism picks up and turns into the proteins and RNA that make the virus work.
/. article.
It's the reverse transcription process that has a high error rate, which is why HIV's rate of mutation is so high. This results in a lot of nonviable DNA, but the virus takes years to work anyway. Eventually, some of these mutations result in a change in the proteins that are attacked by the various HIV drugs so that those drugs no longer work.
As for whether your statement about knowledge in treating various types of viruses is true or not, I don't know, but scientists do know an awful lot about HIV in particular. Each drug is meant to target a specific protein coded by the virus's genome. Being able to use drugs to target a "weak spot" (a spot that is brittle versus mutation) in the genome directly would be a major coup against the virus. This would be a great application for the grid computing mentioned in an earlier
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They're not exactly tough to dig up these days if you know how to use google, so I must assume that you did not even do a rudimentary search for yourself before believing that documentary you watched.