Chinese scientists claim they have developed an infrared light-based, remotely-controlled gene-editing tool that can target and kill cancer cells with precision.

A team led by Professor Song Yujun from the Nanjing University’s College of Engineering and Applied Sciences designed an infrared light-responsive nano-carrier to be used for the CRISPR-Cas9 gene-editing tool, which will have great potential in cancer therapeutics.

The strong penetrability of infrared light enables scientists to precisely control the gene editing tool in deep human tissue.

The CRISPR-Cas9 technique allows genetic materials to be added, removed or altered in particular locations in the human genome. But it remains a challenge in precision medicine worldwide due to the off-target effect of the gene-editing tool, like causing mutation or even cancer in healthy cells due to the inaccurate excision of genes.

The new technique developed by Song’s team has been tested on lab rats with tumors, whose progression was delayed about 20 days after the rat was treated with the new technique.

“Using infrared light, the new technique can precisely alter or cut the designated spot in the genome, improving the target effect of the existing gene-editing tool,” Song told the People’s Daily.

But he said the new technique would still be far from human clinical trials due to concerns like the toxic effect of nano materials and that his team also needed to determine the amount of infrared light needed for curing cancers in humans. A thorough ethics review is also mandated by Chinese authorities.

Last year, Chinese biologist He Jiankui used the CRISPR-Cas9 tool and altered the CCR5 gene of human embryos in a morally deplorable experiment that led to the birth of the world’s first gene-edited babies.

China has tightened scrutiny of biomedical technology after the birth of the gene-edited twins shocked academia. The country updated a law on biomedical technology in February, which mandated high-risk clinical research projects including gene-editing must be approved by the National Health Commission, with both academic and ethics reviews as the prerequisite for clinical trials.