Comment a specific gene in humans HAS been ID'd (Score 1) 464
The quote from the Swedish group didn't make a lot of sense to me either (I'm a biochem grad student). But I read the abstract of their paper(I can't get the full paper right now)and it makes a bit of sense now. Unfortunately coverage of science in the popular press mostly sucks.
The chimp data point to the same genes being involved in human immunity. That must be what they mean by "it may explain why some humans who are repeatedly exposed to HIV don't get sick," that these humans similarly have specific versions of these genes. I have to wonder how closely the human genes resemble the chimp ones and whether we could identify immune humans based on how their genes compare to chimps. Most chimp genes have the identical amino acid sequence as their human counerparts so it seems like it should be elementary to compare the chimp sequences with that from humans who have been repeatedly exposed but resist infection and/or disease (these people exist and looking at their DNA sequence has previously helped explain some things about HIV infection). But maybe these genes are divergent between humans and chimps?
That these genes play a role in HIV immunity is not that surprising. They are one of the cornerstones of the immune system's defenses against viral infection.
The news story doesn't do anything to try to explain what these genes are which takes the punch and the rationale out of the story.
If there's no other big news and the right people think this is interesting enought it might make next tuesday's NYT science section. They'll do it justice (esp. if Gina Kolata is still there).
A slightly pedantic complaint - in a diverse population, those individuals that survived WERE already immune, they didn't make it through and then develop immunity and pass that immunity on to their children- that's Lamarckian, you know Lamarck, the guy who's mostly remembered for being wrong about how evolution works.
I also recall that there IS a specific gene that has been implicated in human immunity to HIV. Individuals bearing two defective copies of a particular receptor protein that sits in the cell membrane (CKR5) and is required for viral entry were immune to HIV after repeated exposure (these people had already exposed themselves through IV drug use or unprotected sex - this wasn't an experiment) and cells from these individuals were immune to infection in vitro.
(Cell 1996 Aug 9;86(3):367-77)
The chimp data point to the same genes being involved in human immunity. That must be what they mean by "it may explain why some humans who are repeatedly exposed to HIV don't get sick," that these humans similarly have specific versions of these genes. I have to wonder how closely the human genes resemble the chimp ones and whether we could identify immune humans based on how their genes compare to chimps. Most chimp genes have the identical amino acid sequence as their human counerparts so it seems like it should be elementary to compare the chimp sequences with that from humans who have been repeatedly exposed but resist infection and/or disease (these people exist and looking at their DNA sequence has previously helped explain some things about HIV infection). But maybe these genes are divergent between humans and chimps?
That these genes play a role in HIV immunity is not that surprising. They are one of the cornerstones of the immune system's defenses against viral infection.
The news story doesn't do anything to try to explain what these genes are which takes the punch and the rationale out of the story.
If there's no other big news and the right people think this is interesting enought it might make next tuesday's NYT science section. They'll do it justice (esp. if Gina Kolata is still there).
A slightly pedantic complaint - in a diverse population, those individuals that survived WERE already immune, they didn't make it through and then develop immunity and pass that immunity on to their children- that's Lamarckian, you know Lamarck, the guy who's mostly remembered for being wrong about how evolution works.
I also recall that there IS a specific gene that has been implicated in human immunity to HIV. Individuals bearing two defective copies of a particular receptor protein that sits in the cell membrane (CKR5) and is required for viral entry were immune to HIV after repeated exposure (these people had already exposed themselves through IV drug use or unprotected sex - this wasn't an experiment) and cells from these individuals were immune to infection in vitro.
(Cell 1996 Aug 9;86(3):367-77)
