Comments on RRResearch: Here's the gel photo

Consider it a belated comment on the original pape...

2012-01-22T11:08:47.424-08:00

Consider it a belated comment on the original paper (and one which the reviewers should have made, since it's an afternoon's worth of work).

Sure, there's no reason to believe that it's mostly As, but does it really matter whether it's zero or 1 in 1000? Either way, it's not a means of alleviating or significantly reducing the need for P.

Since there are so many other lines of evidence sh...

2012-01-20T20:58:57.523-08:00

Since there are so many other lines of evidence showing that As has not replaced most of the P in the DNA backbone, a restriction digest didn't seem worth the trouble.

I really meant that it was one of the first things...

2012-01-18T19:11:21.115-08:00

I really meant that it was one of the first things that I would do if were going to claim that As had replaced P more or less completely. If it were As-DNA, it might not cut (other nucleases could be tried as well; nuclease resistance would be worth noting). If it did cut, As-DNA might run differently than regular DNA (we can't tell from the gel in the original paper because it lacks restriction digests). The second point could be further pursued with Southern blots.

Why would you do that? This is genomic DNA, and...

2012-01-18T18:55:40.136-08:00

Why would you do that?

This is genomic DNA, and a restriction digest would typically produce about 1000 poorly resolved fragments. And cutting the DNA into shorter fragments would reduce the ability to detect random breakage.

Have you done restriction cuts and run the results...

2012-01-18T17:36:44.935-08:00

Have you done restriction cuts and run the results on a gel? That would be one of the first things that I would do.