Science pulls the famed 2011 study on GFAJ-1, reigniting debate over scientific standards and editorial authority.
This 2010 NASA photo shows Mono Lake and microbe GFAJ-1 from a study on “arsenic life.” The study was retracted by the journal Science in July 2025 after being disproven by follow-up studies. Credit: NASA
- The journal Science retracted a 2011 paper claiming the discovery of an arsenic-based lifeform (GFAJ-1) due to experimental flaws and subsequent studies contradicting its main conclusions.
- Initial criticism focused on the instability of a hypothetical arsenic-based DNA backbone and potential phosphate contamination in the original experiments.
- Follow-up research demonstrated that GFAJ-1 did not incorporate arsenic into its DNA, confirming concerns about data quality and interpretation.
- While the journal cited expanded editorial standards justifying retraction, the original authors contested the decision, arguing that it sets a problematic precedent for interpreting scientific disagreements.
In a major editorial decision, the journal Science has officially retracted a famous and fiercely debated 2011 paper that proposed the existence of an “arsenic-based” life-form.
The original study claimed that a microbe, GFAJ-1, isolated from California’s arsenic-rich Mono Lake, could grow by substituting the toxic element arsenic for phosphorus. The provocative claim challenged a fundamental tenet of biochemistry and drew immediate and sustained criticism from the scientific community.
For the journal and many critics, the retraction was a necessary, if delayed, correction of a flawed public record. But the original authors (and some supporters) say it represents an editorial overreach that punishes a provocative hypothesis that should have been left for the community to judge over time.
A provocative claim
The controversy began with a high-profile NASA press conference announcing the findings as a breakthrough in astrobiology, even before the paper appeared in its June 2011 print edition. Acknowledging the immediate and intense skepticism, Science published the paper alongside eight critical “technical comments” and a response from the authors.
Critics initially raised two primary objections: Chemists argued that any arsenic-based DNA backbone would be too unstable to survive, and microbiologists pointed out that the bacterium could actually have been growing off of traces of phosphate contamination in the lab experiments.
By July 2012, subsequent studies published in Science, using the GFAJ-1 strain provided by the authors, concluded that the bacterium did not incorporate arsenic into its DNA. These studies argued that the original findings were based on flawed data, likely resulting from insufficient purification and sample contamination.
Rosie Redfield, a microbiologist at the University of British Columbia and a prominent critic, expressed relief, telling Nature, “It’s good that it’s done,” to prevent the study from misleading future researchers.
The journal’s editor-in-chief, Holden Thorp, noted that the decision reflects expanded editorial standards, where retraction is justified if experiments do not support their main conclusions, even without scientific misconduct. In a public statement, he added, “With this retraction — and with all retractions and corrections — we acknowledge and take responsibility for the role that we played in the paper’s publication.”
Not backing down
However, the paper’s original authors are pushing back. In a public statement published by Science alongside the retraction notice, 10 of the 11 living authors of the original paper declared, “We do not support this retraction,” arguing that their data was peer-reviewed, accurately reported, and sparked productive research.
They say that the journal is overstepping by retracting a paper based on a dispute over interpretation rather than clear evidence of error, data fabrication, or falsification, the traditional standards outlined by the Committee on Publication Ethics (COPE). The authors contend that their work is being singled out under a new, ill-defined standard.
“Disputes about the conclusions of papers, including how well they are supported by the available evidence, are a normal part of the process of science,” the authors wrote. “Claims should be made, tested, challenged, and ultimately judged on the scientific merits by the scientific community itself.”
This view finds some support from others like NASA scientist Mary Voytek, who said the journal’s retraction “doesn’t serve any purpose.”
The episode leaves a central question for researchers and publishers: where is the line, and who ultimately has the authority to draw it?
