Felisa Wolfe-Simon (of arsenic infamy) is no more convincing in person than in print

I went to an informal seminar today at Berkeley by Felisa Wolfe-Simon, the lead author on the much criticized 2010 Science paper “A bacterium that can grow by using arsenic instead of phosphorus”.

I went because, as bad as I thought her paper was, as poorly as I thought she handled concerns expressed about the work, and as cringe-worthy was her performance in the NASA press conference, I understand that sometimes people get caught up in things that are out of their control, and I hoped that in a more comfortable setting she might reveal a different side.

And I have to say, I loved how enthusiastic she is about her  subject. The ways in which microbes elaborate on the basic chemical processes of life are fascinating – although I’m not sure they tell us much about extraterrestrial life (if we find aliens, and they’re just like us except they use arsenic instead of phosphorous, I am going to be disappointed that they’re so similar). And despite the many good arguments for why arsenic in DNA shouldn’t work, I don’t think it’s crazy to remain open to the possibility that they exist.

What I and others found so frustrating about her Science paper was the sense that Wolfe-Simon and her colleagues did not take seriously the task of actually proving that their bug was really using arsenic. Nonetheless, as her talk progressed into the arsenic data, I held out hope that the criticism of the paper would have led to a more sober assessment of her data. Unfortunately, that was not the case.

The most highly-criticized aspects of the paper remained in her talk – with little change or explanation. Too much was made of how radio-labeled arsenic partitioned in a phenol-chloroform extraction. The gel supposedly of GFAJ-1 DNA still had a weirdly well-resolved single band. And the key test of arsenic incorporation was done on a highly impure sample. I asked her about this later point during the Q&A. And she gave the astonishing answer that they lacked the equipment needed to purify DNA. I find it hard to believe Wolfe-Simon thinks you need an HPLC to separate agarose from DNA – a google search for “DNA purification” reveals many simple alternatives. But even if she does think this, her failure to investigate alternatives means means she is not serious about answering the question. And the alternative she proposed – scanning the whole gel at the synchrotron – is hardly a simple alternative, and wouldn’t address the criticism at all.

The clear sense I got from listening to her talk is that she is 100% sure that GFAJ-1 has arsenic in its DNA, and since she does not feel the need to prove it to herself, she feels only mildly compelled to prove it to others. Of course she could be right – as much as her poorly controlled experiments fail to demonstrate that arsenic is incorporated into DNA, they don’t disprove it either. And the publicity that her paper received means that the right experiments will almost certainly be done at some point – if not by Wolfe-Simon then by others. And we will know. If she’s right, the sloppiness of these initial experiments will likely be forgotten and she will be praised for sticking with an unpopular idea in the face of withering criticism. But what will happen if she is wrong, as has to be considered the more likely possibility?

The acid test of a scientist is how they respond when their work is criticized. The best scientists listen and consider what is being said, defend the things they still believe and, most importantly, recognize where their work fell short and use criticism to make their work better. This is, of course, not always so simple. It’s easy to get defensive instead – to view criticism as an attack, see sinister motives in its sources, and ignore its substance.

But I think the worst response is to view criticism as a kind of virtue. And there were signs in Wolfe-Simon’s talk that she is beginning to relish the role of the iconoclast. She appears to see herself as someone who has unconventional ideas that the scientific community can’t deal with. And that criticism of her work is not an effort to get at the truth but a conspiracy to suppress it. At several points she made reference to other scientists whose ideas were not accepted when they were proposed, but which turned out in the long run to be correct. The problem is that many people get stuck this way – and being iconoclastic becomes their whole scientific identity (we can all think of people like this….).

It would be a real shame if this happened to Wolfe-Simon. She seems affable and completely sincere. I’m sure she is, in many ways, a capable scientist. And, as I said above, it’s hard not to be drawn in by her enthusiasm for her subject. Science needs people who challenge the limits of what we know and believe, and who seek weird things in the natural world. And there is no doubt that Dr. Wolfe-Simon has discovered a species that does unusual things with arsenic. As the hoopla over this work dies down, I hope Dr. Wolfe-Simon spends less time at TED and more time doing the experiments that will compellingly demonstrate what GFAJ-1 is really all about.

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  1. Titus Brown
    Posted March 19, 2011 at 6:39 am | Permalink

    Well said. I’m always disappointed when I don’t get good, critical questions; it means that I’ve either failed to explain what I’m actually doing, OR people don’t think it’s interesting enough to engage with intellectually. Either way, failure! (The third alternative is that I’m just that good, but the evidence is against 😉

  2. Posted March 19, 2011 at 8:51 am | Permalink

    Thanks so much for taking the time to write this up, and for sharing it! I think your perspective is basically the same as mine, except I wonder more about the people who are mentoring and promoting her. Shouldn’t they have known better? Obviously Paul Davies doesn’t know what would constitute compelling evidence in this area, but if it’s a Big Question topic, why can’t they be bothered to get the basics right?

  3. MK
    Posted March 23, 2011 at 1:40 pm | Permalink

    The scientific method is easy to forget sometimes. Peer reviewers are supposed to keep it rigorous in that sense, right? How did they not force the proper controls to be conducted? And if she hasn’t proved the claim, as you say, how is she herself convinced?

  4. David Sweedler
    Posted April 27, 2011 at 10:14 pm | Permalink

    I would think there are several very sensitive assays for measuring the amount of genomically incorporated arsenic in DNA. Partitioning in a phenol chloroform bilayer is NOT one of them. Purify the genomic DNA by PAGE and then have it run on a ICAP-AA atomic adsorption spectrometer for elemental analysis out to PPB or PPT leveels and see what happens. Should be able to estimate the number of arsenic incorporations per base pair by arsenic to phosphorus ratios. If it is constant for many different isolated bands then you have something that isn’t artifactual.

  5. agonyfIips
    Posted October 17, 2011 at 12:07 am | Permalink

    To the author, having just stumbled upon your page, could you be so kind as to comment to the More recent report, on 27 May 2011, when Felisa Wolfe-Simon and her team responded to the criticism in a followup Science journal publication.



    P.S. I laughed watching her on NASA.

  6. Ex-scientist
    Posted March 22, 2013 at 1:47 am | Permalink

    You are way too gentle. You know in your heart of hearts that she was a gushy second rater. That press conference with the hack NASA manager pumping the thing. Blech. She does NOT deserve a job. GFAJ should be renamed NJFF.

    And you may think I am being harsh for the fun of it…but she is really bad news. And the minority scholarship…sigh.

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