Controversial arsenic-based DNA paper retracted by Science journal 15 years after publication amid altering retraction requirements

A controversial 2010 paper claiming to have found micro organism substituting arsenic for phosphorus in its DNA has been retracted by the journal Science. While fraud is just not suspected, the transfer was warranted 15 years after its publication as a result of adjustments in retraction standards, says Science’s editor-in-chief, H Holden Thorp.

The research, funded by Nasa, made outstanding claims concerning the bacterium GFAJ-1, discovered within the saline and arsenic-filled Mono Lake in California. When the pressure was cultured with out phosphorus and in excessive arsenic concentrations, the crew detected arsenate that it believed was related to the bacterium’s DNA.

The findings had been met with scepticism, and solely revealed in print in 2011, alongside eight technical comments. In 2012, two papers unsuccessfully tried to duplicate the outcomes, concluding that though the microbe may tolerate arsenic, it was not integrated into its DNA.

Critics believed the findings had been the results of arsenic contamination of the analysed nucleic acids, as a result of inadequate purification. In the retraction, revealed on 24 July, Thorp states that regardless of the early rebuttals, at the moment the journal reserved retractions for circumstances of deliberate knowledge manipulation. He says that since then, ‘standards for retracting papers have expanded’ and a retraction is justified ‘if the editors determine that a paper’s reported experiments don’t assist its key conclusions’. The resolution was based mostly on pointers from the Committee on Publication Ethics (Cope).

Authors protest

Ten of the papers’ co-authors signed a letter stating they stood by their findings and accused Science of exceeding its authority. Speaking to Science news, co-author Ariel Anbar, an isotope geochemist at Arizona State University, mentioned ‘the actual dispute is about how the info is being interpreted, which shouldn’t be grounds for retraction however is authentic scientific debate.

Nicholas Williams, an skilled in phosphate ester hydrolysis on the University of Sheffield, UK, says a lot blame lies with the journal itself and poor refereeing that ignored each chemical ideas and certain experimental flaws. ‘Rewriting the way DNA could be formed at a fundamental level was a huge overstatement,’ he says.

University of Leeds chemist, Terence Kee, who additionally has an curiosity in astrobiology, says it could technically be attainable for a DNA construction to type with arsenic, though it’s bigger than phosphorus. ‘Arsenic as an element is in the same group as phosphorus, it has the same kind of chemical structure and chemical bonding,’ he notes. But it types a lot weaker bonds to oxygen, in contrast with phosphorus, so arsenic-based DNA can be much less steady and vulnerable to degradation. It’s unclear if such a construction would have the ability to operate in the identical method as DNA, he provides.

In 2012, Jerzy Leszczynski and colleagues from Jackson State University within the US ran a computational research to take a look at the structural feasibility of such a polymer. They discovered that base-stacking may enhance the resistance of arsenate to hydrolysis, however it was nonetheless much less steady than typical DNA. Leszczynski says there could also be some particular situations that may permit nature to utilise such a compound. ‘It is quite interesting and possible, even if the published experiments might not provide a final answer.’

By 2012, a number of publications urged various explanations for the way these micro organism develop in low-phosphorus and high-arsenic situations, which might be lethal to most organisms. Dan Tawfik from the Weizmann Institute of Science in Israel examined a protein that mediates phosphate uptake within the Mono Lake GFAJ-1 pressure and located it was 10-times more sensitive to phosphorus than arsenic, in contrast with different micro organism. Another research urged that arsenate induces ribosome degradation, which supplies the lacking supply of phosphate, with a small variety of arsenate-tolerant cells in a position to survive.

Still controversial in any case this time

Several researchers contacted nonetheless felt the retraction was controversial after 15 years. ‘Given nothing new [has] arisen, why forcibly retract the article now?’ says Williams. ‘I think that the world of science is not being misled … this retraction seems a needless step.’

Thorp admitted that the retraction was precipitated by the publication in February this 12 months of a New York Times profile of lead author Felisa Wolfe-Simon, then on the Nasa Astrobiology Institute. The intense criticism she obtained in 2010 led her to depart science, solely returning part-time in 2024.

Ivan Oransky, co-founder of Retraction Watch, says he additionally has questions on why the research was retracted now. He thinks this could have been carried out a lot earlier and says the retraction is ‘entirely consistent with Cope and other guidelines going back well over a decade and longer than this paper was published’.

Kee stays ambivalent concerning the present retraction. ‘I would have rather seen it left in the scientific record with the subsequent trail [of responses] being able to link to the original paper.’ But he nonetheless thinks it could be an attention-grabbing undertaking for a chemist to attempt to synthesise an arsenic-based DNA double helix simply to see what is perhaps attainable.