2 replies to this topic

[manofsan]

Read this:

http://www.nature.co...l/050314-7.html

One of the things that intrigues me is how silencing of the 2nd X-chromosome is accomplished.

I'm wondering if this type of feature would be useful for silencing mutant DNA, for example in the scenarios we were previously discussing about partial re-population/rehabilitation of mtDNA in mutant mitochondria.

Any comments on how the silencing is done?

Furthermore, would there be any complications in repopulating nuclear DNA in women as compared to doing it for men? (assuming it can be done, of course)
Would there be any complications specific to women in the proposed migration of mitochondrial genes to nuclear DNA?

I guess we know that women are supposed to be longer lived than men partly because they have that backup X-chromosome in case genes on the primary X-chromosome fail. Hey, does that mean that women can survive radiation exposure better than men can?

But we all have the same mtDNA, regardless of gender. So that means that women's mtDNA can burn out just as fast as men's doesn't it? Supposing we overcome the weakness of mtDNA susceptibility to ROS damage within the mitochondria through some successful therapeutic technique -- that only leaves nuclear DNA damage as the next main vulnerability. With women having the extra backup X-chromosome, this should then really allow them to outpace men in longevity, and "separate the men from the boys" -- or in this case, separate the girls from the boys.

Comments?

[John Schloendorn]

Furthermore, would there be any complications in repopulating nuclear DNA in women as compared to doing it for men? (assuming it can be done, of course)

Heh, there would generally be so incredibly many problems that in my opinion you should better forget the idea real quick ;-) But I don't think a large part of these problems would derive from a fraction of x-chromosomal genes being doubly expressed, since females who were partially repopulated with male stem cells are doing just fine.

Would there be any complications specific to women in the proposed migration of mitochondrial genes to nuclear DNA?

Nah, just stick'em elsewhere...

Have any of the doubly active x-chromosomal genes been shown to be longevity associated?

[manofsan]

Well, I dunno about any specific gene, but in general apparently having the backup genes from the extra X-chromosome means women can fall back on them if their primary genes conk out.