The long-debated research announcing the existence of an arsenic-eating microbe has officially been retracted by the journal Science, 15 years after its publication due to issues with contaminated and faulty data. Interestingly, the authors still defend their original findings.
This peculiar microbe, known as GFAJ-1, was collected from the arsenic-heavy, saline waters of Mono Lake in California by a research group spearheaded by Felisa Wolfe-Simon from NASA’s Astrobiology Institute.
Wolfe-Simon and her team conducted experiments where they managed to sustain the growth of GFAJ-1 in petri dishes, using arsenic in place of phosphorus—an essential building block for DNA that typically spells toxicity for organisms. Their findings were presented in the prestigious journal Science back in 2010.
Prior to the revelation of this paper, NASA buzzed with excitement, announcing plans for a press conference that would spotlight groundbreaking evidence in the search for extraterrestrial life. Soon, the discovery of GFAJ-1 gained massive attention and was recognized as a significant advancement in astrobiology, challenging long-standing views on what constitutes life and suggesting that “arsenic life” might even exist.
Wolfe-Simon expressed the significance of their discovery with enthusiasm, stating in a 2010 NASA statement, “We have stumbled upon a microbe that constructs part of its makeup from arsenic, which is quite the revelation. This prompts us to wonder what else life is capable of here on Earth that remains unseen!”
Nevertheless, almost immediately, skepticism arose regarding the study. By the time the research was published in the 2011 print edition of Science, a total of eight external expert commentaries highlighted significant scientific shortcomings in both methods and interpretations.
In 2012, two studies were published within Science, attempting to replicate results associated with the arsenic-eating claims. Both studies demonstrated that while GFAJ-1 can endure substantial levels of arsenic, it cannot replace phosphorus as a pivotal component for life.
Though the controversial “arsenic life” study faced challenges in replication, it was never officially invalidated for issues related to intentional deception or malpractice. However, over the last five years, Science has begun retracting articles for reasons apart from outright fraud. Thus, on July 24, the journal decided to pull Wolfe-Simon’s study.
According to Valda Vinson, executive editor of Science publications, one of the Technical Comments pointed out inadequacies in purifying the nucleic acids evaluated. In light of evidence indicating the results stem from contamination, the editors concluded that the centerpiece conclusion posited in the original paper cannot be supported due to compromised data.
Still, the study’s authors disagree with the retraction, asserting that, “Differences of opinion regarding research conclusions—for how well they align with available evidence—are commonplace in scientific discourse,” as mentioned in their eLetter released on the same day. They conveyed, “While perhaps our work could have benefitted from deeper scrutiny and discussion, we affirm confidence in the data as presented.”
