A Chinese biologist says he has carried out more work in his laboratory to support his controversial claims that he has developed a new tool to engineer genes, including those of people and animals.
Han Chunyu and his colleagues at the Hebei University of Science and Technology said in May they had used a genetic mechanism in the bacteria NgAgo which allowed them to edit and alter the genes of other species.
Han’s findings appeared to provide further evidence of the dawn of a biotechnology revolution – the future ability to reprogram genes at will, which could solve problems like cancer and ageing.
The findings were originally hailed by other scientists as a breakthrough, but doubts were raised after other researchers around the world have been unable to replicate his results in their own laboratories.
Han said in an interview with the Chengdu Economic Daily published on Monday that the confusion was caused because he had used a batch of the bacteria which was later destroyed after a refrigerator storing the samples was hit by a power cut.
Other laboratories around the world may have been using slightly different strains of the bacteria while trying to replicate his findings, he was quoted as saying.
He later repeated the experiment with samples of NgAgo bought from an American-based supplier and was ultimately able to repeat his results in early October, he said.
He has since able to repeat the experiments and results “four or five” times in the following weeks, with mostly positive the results, according to Han.
“The information will be released soon,” he was quoted by the newspaper as saying.
Many laboratories had requested strains of the bacteria after his paper was published, but he could not provide them because of the power cut in the fridge, he said. The result was their results differed from his team’s, he was quoted as saying.
Other scientists, however, have greeted Han’s latest statement with caution.
A research paper by numerous teams overseas has been submitted to the scientific journal Nature Biotechnology, which published the original research.
More than a dozen mainland laboratories have also submitted a paper to another journal on Han’s research. They both challenge his team’s claims about the effectiveness of the NgAgo technology.
“The research community has reached a consensus that Han’s paper is plagued by serious problems. Now everyone’s waiting for the hammer of a final verdict to slam down, for the journal to withdraw his paper, for the redemption of China science’s reputation,” said a mainland scientist who asked not to be named.
Han did not reveal any technical details of his recent work in the laboratory, but told the newspaper the results strengthened his confidence in the NgAgo genetic editing tool technology, even if the rest of the world disputed the research.