Nobelist Linda Buck retracts two studies on olfactory networks — and the news is embargoed

Well, it’s happened: The Embargo Watch and Retraction Watch worlds have collided. I had initially figured on two posts here, but it soon became clear that how journals were handling these retractions, using embargoes, was central to both. So this is being cross-posted on both blogs.

Linda Buck, who shared the 2004 Nobel Prize in Physiology or Medicine, has retracted two papers published in 2005 and 2006. Both retractions — one in the Proceedings of the National Academy of Sciences (PNAS) and one in Science — appear online today.

The papers describe how nerves that carry information about scents connect from the nose to the olfactory bulb, where they are processed. They were published after the 2004 Nobel, which was for discoveries “of odorant receptors and the organization of the olfactory system.”

The retractions come two and a half years after Buck retracted a 2001 Nature paper co-authored with Zhihua Zou, a post-doc in her then-Harvard lab. She’s been at the Fred Hutchinson Cancer Research Center since 2002, and is a Howard Hughes Medical Institute investigator. In 2008, Nature’s news section reported:

Harvard Medical School has formed an ad hoc committee to review the retraction, and Buck has asked the Fred Hutchinson Cancer Research Center to review two later publications on which Zou was the lead author. “It’s disappointing of course,” says Buck. “The important thing is to correct the literature.”

The PNAS and Science retractions are of those two later publications. The PNAS study was cited 61 times, and the Science study was cited 73 times, according to the Thomson Scientific Web of Knowledge.

The Science retraction reads:

In the Report “Combinatorial effects of odorant mixes in olfactory cortex” (1), we described subcellular patterns of Arc (arg3.1) mRNA expression in anterior piriform cortex neurons after mice had been exposed to odorants. We reported that some cortical neurons express Arc in response to a mix of two odorants but not either odorant alone. My laboratory has been unable to reproduce this finding. I am therefore retracting the Report. I sincerely apologize for any confusion that its publication may have caused. Z.Z. declined to sign this Retraction.

Zou — who denied wrongdoing in response to the 2008 Nature retraction and stood by the paper — was most recently at the University of Texas Medical Branch (UTMB) at Galveston. Although Zou’s faculty page still appears on UTMB’s website, he has not been employed by the school for two years, according to its public affairs office. He was one of 2,400 layoffs following Hurricane Ike in 2008, and his current whereabouts are unknown.

Here’s how the Hutchinson Center responded to questions we sent Buck:

In 2008, Dr. Linda Buck at Fred Hutchinson Cancer Research Center retracted a paper she and her co-workers had published in Nature in 2001 describing experiments on the mouse olfactory cortex done by a former postdoctoral researcher in her lab, Dr. Zhihua Zou. Buck and her colleagues subsequently reviewed two other papers her lab had published describing Zou’s experiments on odor responses in olfactory cortex, one published in PNAS in 2005 and the other published in Science in 2006. They were unable to reproduce key findings in both papers. In addition, they found figures inconsistent with original data in the PNAS paper. Buck has therefore simultaneously retracted both the PNAS and Science paper. She regrets any confusion that has resulted from the publication of these papers and thanks the colleagues who painstakingly worked with her to duplicate these experiments and evaluate the data.

We also tried to find out whether Nobel Prize committees keep tabs on retractions by Nobelists. The committees responsible for the physics and chemistry prizes, and in economics, probably don’t, we were told, but we haven’t heard back about medicine or physiology.

Now for the embargo angle. This post is going live as the embargo on the Science retraction lifts, at 2 p.m. Eastern today. The retraction was included in Science’s weekly embargoed materials, sent to reporters on Sunday night. That means it was accepted sometime before Sunday night, but the journal decided it would be best to embargo it and send it to reporters.

We weren’t sure if that was standard practice, or just because this was going to be a high-profile retraction. When we asked Science about that, press packet director Kathy Wren said it was standard practice.

To fact-check that, we looked at what Science has done for the past two years (and shared this with my former colleagues at The Scientist): There have been three retractions in Science during that time (not including this new Buck one). For the two in 2009, they did exactly the same thing as they’re doing now. For the one in 2008, they did not include it in the press packet. That issue’s full table of contents, included with the press packet, points to another issue for some reason, so it’s possible they may have included it without making a note of it in the press packet. That’s certainly different from what they’ve done here, but it does seem true that retractions are “generally included” in press materials.

But at the time of this posting, we still haven’t seen the PNAS retraction, which is also scheduled to go live at 2. We only found out about the retraction when the Hutchinson Cancer Center mentioned it in their embargoed comments. We confirmed with PNAS when it was running, but they wouldn’t provide the actual text. (Now that it’s live, expect an update on this post in a little while.) See update at the end of this post.

This seemed strange to us, so we asked PNAS managing editor Daniel Salsbury for the rationale. Here’s our exchange, sans salutations:

RW/EW: Will you be providing a copy of the Buck retraction embargoed until 2 p.m. yesterday? Is that embargo time because of the Science embargo?

PNAS: As a matter of policy, we do not provide advance copies of retractions or corrections to the media. The retraction statement will appear tomorrow afternoon in PNAS Early Edition (http://www.pnas.org/content/early/recent) coinciding with the publication of the Science statement.

RW/EW: Thanks. What’s the rationale behind the policy? I can understand publishing these as soon as they’re ready, but this one is embargoed and yet unavailable to the media for advance reporting.

PNAS: To be clear, we do not embargo retractions or corrections and we do not provide advance copies to the media as we do for research articles.

RW/EW: I understand the last part, but I guess we have a different definition of “embargo.” The retraction is accepted and and finalized, yet being held until tomorrow. To me, that’s an embargo. But I appreciate your quick and forthright responses. Thanks.

We’re still stumped as to how this is an embargo, but maybe a reader can help us figure that out. Even if it’s just semantics, though, how is science or journalism served by holding an accepted retraction for another journal’s embargo time? Releasing retractions as soon as they’re ready to go seems like the best thing, although Science’s approach is also consistent, provided there wasn’t a huge delay between acceptance and release.

Perhaps PNAS was hoping no one would notice, but that was unlikely given all the attention paid to a Nobelist’s retraction — not to mention that once the Hutchinson Center mentioned the PNAS retraction, we were all going to be asking PNAS for it.

As always, the comment thread is open.

Update, 2:55 p.m., 9/23/10: The PNAS retraction has just been posted. Text:

Retraction for “Odor maps in the olfactory cortex,” by Zhihua Zou, Fusheng Li, and Linda B. Buck, which appeared in issue 21, May 24, 2005, of Proc Natl Acad Sci USA (102:7724–7729; first published May 23, 2005; 10.1073/pnas.0503027102). The undersigned authors wish to note the following: “This article described patterns of c-Fos labeling in anterior piriform cortex following exposure of mice to odorants. In efforts to replicate this work, we have observed c-Fos in sparsely distributed neurons, as reported, but we have found no evidence for the reported finding that odorants induce related patterns of c-Fos labeling in the two hemispheres and in different individuals. Inconsistencies have also been found between several images shown in the paper and the original data. Because of these discrepancies, the undersigned authors are retracting the article. We sincerely apologize for any confusion it has caused.”
Fusheng Li
Linda B. Buck