Preposterous Universe

 
Live from Irvine

If you're wondering why posts from the last few weeks are lacking a certain, you know, "substance," it's because I've been traveling like crazy. Right now I'm in Irvine, California, at the National Academy of Sciences ("Home of Studies that are Increasingly Ignored"), for a Japanese-American Frontiers of Science meeting. They bring together young (-ish) scientists from the two countries, in various fields, to share the wonders of their research. The good news is that they have wireless internet all over the place. So we're livebloggin', baby!

Except that, not being an expert in the talks, I can't really report accurately what we are hearing. This morning we heard about the geological (areological?) history of Mars, especially as it was influenced by the presence of water. There is very good reason to believe that Mars used to be filthy with the stuff, so we'd like to know where it all went. The Earth could someday end up like that.

Right now we are hearing an extremely amusing talk on cloning by Teruhiko Wakayama. His group was the second to clone mammals; they cloned multiple generations of mice shortly after the first mammalian clone, Dolly the sheep. Clones should be boring -- they're just genetic duplicates of the parent, just as twins are duplicates of each other. But there's more to life than genetics! It turns out that clones tend to be overweight and die young, on average. You might think that the cloning process had somehow messed up the DNA. But, interestingly, when the clones have offspring via ordinary sexual reproduction, they come out perfectly normal! Here I am far outside my expertise, but the point seems to be that the expression of the genetic information is somehow disrupted by the cloning process, but the children of the clone are okay.

(The one thing I remember from a similar meeting last year is that female clones are effectively not genetic copies of their parents. Each individual uses the same amount of genetic information, but the X chromosome has more information than the Y. So the men (XY) use all the information they have, but the women (XX) will randomly turn off some fraction of the data in their X chromosomes while they are still embryos. There are something like 2⁵⁰ possible outcomes. So, for example, you can clone a female cat, but the kittens will all have different colorings.)

On Sunday I'll be giving a talk on cosmology, along with Hitoshi Murayama and Naoshi Sugiyama. Still need to decide what I will talk about. Tomorrow I might skip the talks and go Xmas shopping.

~ posted by Sean Carroll at 4:29 PM ~ link ~ ~ ~