CAIXIA GAO: Crop engineer

A gene-editing specialist seeks to make her mark by improving key agricultural plants. 

By Heidi Ledford 

Illustration by Paddy Mills

Plant biologist Caixia Gao was initially reluctant to take up gene editing using CRISPR–Cas9 — the technique that is sweeping through biology laboratories around the world. Her lab had already made mutations in 82 genes using an older technology, and the thought of switching to something new was daunting. “At first I felt some resistance,” Gao says. “And then we decided: well anyway, we have to try.”

After a year of frenzied work, her lab at the Chinese Academy of Sciences’ Institute of Genetics and Developmental Biology in Beijing became the first to use the revolutionarily simple gene-editing technique in crops, specifically wheat and rice (Q. Shan et al. Nature Biotechnol. 31, 686–688; 2013). “If there’s any lesson we learn in genome engineering, it’s that you have to be very flexible and adapt to technology that changes every day,” says Daniel Voytas, a plant biologist at the University of Minnesota in Saint Paul. “Caixia has that ability to adapt.”

She has been doing that for her whole career. Gao went to university planning to go into medicine, but was redirected to agriculture. “Not my interest at all,” she says. “But my thinking is always: as long as I am in this position, I will do my best.” After a PhD in grassland ecology, Gao switched again by taking up plant genetic engineering at the seed company DLF in Roskilde, Denmark.

Gao had to develop methods for inserting foreign genes into grass, which was frustrating work, says Klaus Nielsen, research director at DLF. Many grasses are difficult to engineer, and each species — or even genetic variants within a species — may require its own special mix of growth conditions. Gao is famously cheerful, but there were days when Nielsen could tell that she was seething.

Even so, she pressed on. “Eventually, she could look in the microscope and see things no one else could see,” Nielsen says. “She was cracking the nut every time.”

During Gao’s 12 years at DLF, she cracked that nut again and again — by genetically altering several traits, including the times when key grass species flower. But European suspicion of genetically engineered crops left her with little hope that her work would leave the lab. “It was so difficult to bring a crop to the market — in the end, the work cannot inspire you any more,” she says. That issue, plus a desire to return with her children to her mother language and culture, sent her back to China.

In Beijing, Gao tackled genetic engineering in wheat, a crop that is legendary for its difficultly to work with, in part because many strains have six copies of the genome. Soon she was considered one of the best in the world at engineering wheat, says Voytas.

Gao is happy with her decision to return to China, where funding for agricultural research is a higher priority than it is in Europe, she says. The government has approved some crops developed with early genetic-engineering techniques, but such approvals have slowed, and China has yet to decide how it will regulate gene-edited crops.

Still, Gao is hopeful that some of her creations will reach the market. Meanwhile, a disease-resistant wheat engineered in her lab is being further developed by a company in the United States. Ever the optimist, Gao refuses to accept public fears about genetically modified organisms (GMOs). “If I meet some people in the street and I ask, they will say they don’t want GMO at all,” she says. “And I stop there and educate them. They are so surprised.”