Chinese geneticist Han Chunyu has answered critics and defended the validity of his gene-editing technique after the head of an Australian genetics lab said he was unable to replicate the process despite numerous attempts, China Daily reported.
In early May, Nature Biotechnology, a monthly scientific journal of Nature Publishing Group, came out with Han's paper discussing his research findings on the new gene-editing technology called NgAgo, which immediately attracted international attention.
But three months after its publication, some scientists started to wonder whether the technology is possible since they have been unable to replicate it.
Gaetan Burgio, head of the transgenesis lab of Australian National University, said on his Twitter account Friday, July 29, that he had tried using NgAgo several times but he found no evidence for genome editing.
According to Burgio, the conditions for successful replication were contradicted by Han's paper. He had said earlier in a statement that the gene-editing technology is effective only in editing genes from mice.
Han, an associate professor at Hebei University of Science and Technology, said he would repeat the experiment results, adding that he would reveal the original experimental data if requested by the journal.
"It's like they ganged up against NgAgo," Han was quoted by Chinese media as saying.
In terms of accuracy, efficiency and flexibility, the NgAgo is seen as a better method than the current mainstream gene-editing technique called CRISPR/Cas9. Han said it helps solve the "off-target effect" problem, which is a major issue with CRISPR/Cas9. The NgAgo method is theoretically more accurate, reports said.
The new gene-editing technology could replace CRISPR, once it is widely accepted and confirmed. It would also have a huge impact on business, especially those who have made big investments on CRISPR, according to an opinion published by Qilu Net, a regional news portal in China.
A Beijing researcher told China Daily that it was still premature to judge Han's research findings or give any conclusions.
"That Han's experimental results cannot be replicated so far doesn't mean it cannot be in the future," the researcher said. "The issue should be left to time and peer scientists. Give it at least three to five years."