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Home ›› About Speciation ›› Speciation News

EVISA News revisited: Arsenic, an element of archaic life ?

(26.07.2025)

On December 4, 2010, EVISA reported on a high-profile NASA press conference where Dr. Felisa Wolfe-Simon presented groundbreaking research exploring unconventional biochemistry.

Photo: mage of GFAJ-1 grown on arsenic.
Image Credit: Jodi Switzer Blum

Her team had discovered a bacterium—strain GFAJ-1 of the Halomonadaceae family, isolated from Mono Lake, California—that appeared capable of substituting arsenic for phosphorus in its biomolecules. This raised the extraordinary possibility of life based on alternative genetic frameworks, potentially not reliant on traditional RNA/DNA structures.^[1]

However, the scientific community quickly met these claims with skepticism. The conclusions were heavily criticized in responses to the original publication,^[2] and many researchers expressed doubts about the validity of the findings.^[3] By 2012, two independent studies published in the same journal refuted the central claims of Wolfe-Simon’s work.^[4][5]

On July 24, 2025, the journal Science officially retracted the original 2010 paper.^[6] The retraction cited updated editorial policies and concluded that the experiments failed to support the paper's main conclusions. In a blog post published along with the retraction,^[7] Thorp and Valda Vinson, executive editor of Science, went into further detail: One of the Technical Comments [8] had pointed out that the nucleic acids that were analyzed were not sufficiently purified before the acquisition of spectra that suggested the presence of arsenic. Given the evidence that the results were based on contamination, Science believes that the key conclusion of the paper is based on flawed data.

Despite this, the original authors stood by their findings, publicly disputing the retraction and criticizing the decision as inconsistent with publishing best practices.^[9]

Felisa Wolfe-Simon continues to conduct research at the frontiers of life science, exploring the limits of biology as we know it.^[10]

References

[1] F. Wolfe-Simon, J. Blum, T. Kulp, G. Gordon, S. Hoeft, J. Pett-Ridge, J. Stolz, S. Webb, P. Weber, P. Davies, A. Anbar, R. Oremland, Retracted: A Bacterium That Can Grow by Using Arsenic Instead of Phosphorus, Science, 332 (2011) 1163-1166. DOI: 10.1126/science.1197258

[2] Felisa Wolfe-Simon, Jodi Switzer Blum, Thomas R. Kulp, Gwyneth W. Gordon, Shelley E. Hoeft, Jennifer Pett-Ridge, John F. Stolz, Samuel M. Webb, Peter K. Weber, Paul C. W. Davies, Ariel D. Anbar, and Ronald S. Oremland, Response to Comments on “A Bacterium That Can Grow Using Arsenic Instead of Phosphorus”, Science, 332/6034 (2011) 1149. DOI: 10.1126/science.1202098

[3] Carmen Drahl, The Arsenic-Based-Life Aftermath , Chem. Eng. News, 90/5 (2012) 42-47. https://cen.acs.org/articles/90/i5/Arsenic-Based-Life-Aftermath.html

[4] Tobias J. Erb, Patrick Kiefer, Bodo Hattendorf, Detlef Günther, and Julia A. Vorholt, GFAJ-1 Is an Arsenate-Resistant, Phosphate-Dependent Organism, Science, 337/6093 (2012) 467-470. DOI: 10.1126/science.1218455

[5] Marshall Louis Reaves, Sunita Sinha, Joshua D. Rabinowitz, Leonid Kruglyak, and Rosemary J. Redfield, Absence of Detectable Arsenate in DNA from Arsenate-Grown GFAJ-1 Cells, Science, 337/6093 (2012) 470-473. DOI: 10.1126/science.1219861

[6] H. Holden Thorp, Retraction, Science, 389/6758 (2025) 357. DOI: 10.1126/science.adu5488

[7] Valda Vinson, H. Holden Thorp, The last step in a long process on “arsenic life”, Editor's Blog, Science, 24 Jul. 2025 . https://www.science.org/content/blog-post/last-step-long-process-arsenic-life

[8] Rosemary J. Redfield, Comment on “A Bacterium That Can Grow by Using Arsenic Instead of Phosphorus”, Science, 332/6034 (2011) 1149. DOI: 10.1126/science.1201482

[9] Ariel Anbar, Paul Davies, Gwyneth Gordon, Tom Kulp, Shelley (Hoeft) McCann, Jennifer Pett-Ridge, John Stolz, Jodi Switzer Blum, Samuel Webb, Felisa Wolfe-Simon, Authors’ response to Science’s decision to retract “A bacterium that can grow by using arsenic instead of phosphorus”, eLetters, Jul 24, 2025.

[10] Sarah Scoles, Her Discovery Wasn’t Alien Life, but Science Has Never Been the Same, New York Times, Febr. 14, 2025. https://www.nytimes.com/2025/02/11/science/arseniclife-felisa-wolfe-simon-retraction.html