Redheaded Neanderlady

Redheaded Neanderlady
This is a photoshopped version of something I found in National Geographic about the time I started researching

Sunday, August 10, 2008

John Hawks explains it all

A quick update on the Neandertal genome sequencing news: The John Hawks Weblog has a long post explaining and clarifying a great deal of information about it. Much of the information was confusing to me, and this was partly due to bad science reporting. But then, there are very few science reporters out there, for whom I have a great deal of use, though that is another story. But for those of you who are interested in these kinds of things, you would do very well to click on the link I provided. It's worth the effort of going over there, and reading Dr. Hawks' rather long, but extremely imformative, post.
Anne G

3 comments:

Kim Norton said...

Interesting paper and interesting reaction, too. I do not think the distinctive Neanderthal mtDNA is evidence one way or the other whether Nts interbred with CMs.

The piece on COX2 that John has picked up is interesting for the reasons he has outlined. It could be chance that the amino acid substitutions are the same as in baboons. After all, there are only a limited number of substitutions that can me made without upsetting the structure of the COX2 subunit too much. If the changes in protein efficiency are only slight, then I can see that arguing that they are neutral (as Green et al do) is a fairly safe conclusion.

The trick will be to try to correlate the differences in baboon diet/lifestyle to the functional changes to the COX2 subunit. Cytochrome c is pretty mission critical, and getting a non-functional cyt C will be fatal; a bit like cyanide poisoning!

Kim

Kim Norton said...

Interesting paper and interesting reaction, too. I do not think the distinctive Neanderthal mtDNA is evidence one way or the other whether Nts interbred with CMs.

The piece on COX2 that John has picked up is interesting for the reasons he has outlined. It could be chance that the amino acid substitutions are the same as in baboons. After all, there are only a limited number of substitutions that can me made without upsetting the structure of the COX2 subunit too much. If the changes in protein efficiency are only slight, then I can see that arguing that they are neutral (as Green et al do) is a fairly safe conclusion.

The trick will be to try to correlate the differences in baboon diet/lifestyle to the functional changes to the COX2 subunit. Cytochrome c is pretty mission critical, and getting a non-functional cyt C will be fatal; a bit like cyanide poisoning!

Kim

Anne Gilbert said...

kim:

I assume by "CMs" you are referring to early "modern" Europeans or early "modern" humans. Unfortunately people in the field don't usually use the term "Cro-Magnon" any more, as an analogue for "modern" humans. So it's probably better to use a phrase like "early modern humans" or the like.

That said, I've read the paper, as well as Dr. Hawks' comments on it, and Hawks clarifies a lot, though all I can say for the paper is, it seems to be making contradictory statements and ignoring the overlap between some parts of N mtDNA and "modern" human mtDNA. They were looking for differences and found them. What these differences "mean", I'm not quite sure. They also hinted they were working on Neandertal nuclear DNA. And I wonder how they're going to do that?
Anne G