When Mary-Dell Chilton, then known as Mary-Dell Matchett, enrolled at the University of Illinois in the 1950s, women were discouraged from pursuing careers in science. That didn’t stop her from considering majoring in physics, but falling asleep during boring freshman classes did. She also considered astronomy, but a professor told her she wouldn’t be able to take a class on the subject until her sophomore year.
“To hell with that,” she recalled thinking, in a 2008 interview with Scientific American.
Instead, she chose chemistry. She would go on to become a pioneering figure in agricultural biotechnology, leading the research team credited with creating the first genetically modified plant in 1982 – a discovery that would transform global agriculture.
Dr. Chilton and his colleagues developed a method to insert the genes of a foreign organism into a plant, which would eventually lead to advances such as higher-yielding crops that are resistant to insects and diseases and tolerant of extreme weather conditions.
At her retirement party in 2018, her son Mark Chilton later said, “I asked everyone to raise a glass to the astronomy professor who fired her.” »
Dr. Chilton died June 24 at her home in Carrboro, North Carolina, near Chapel Hill. She was 87 years old. The cause was congestive heart failure, Mr Chilton said.
“She was truly driven by the idea that the world needed the best science it could offer to help humanity feed itself,” Andrew Binns, professor emeritus of biology at the University of Pennsylvania who collaborated with Dr. Chilton on the development of the first genetically modified plant, said in an interview.
Among other prestigious awards, Dr. Chilton received the World Food Prize, likened to a Nobel Prize for food and agriculture, in 2013. Ten years later, she received the National Medal of Technology and Innovation.
“Millions of farmers around the world have Dr. Chilton to thank for protecting their crops from disease, pests and climate shocks,” Tom Vilsack, executive director of the World Food Prize Foundation and former U.S. Secretary of Agriculture, said in a tribute after his death.
About 90 percent of soybeans, cotton, corn and sugar beets grown in the United States are now genetically modified. Although most scientists agree that modified foods are safe to eat, public opinion remains polarized. Questions have been raised about the long-term effects on human health and the environment; how many genetically modified crops actually address climate change concerns; the dangers of corporate monopolies over the seed supply; and the extent to which the promised higher agricultural yields have been realised.
For his part, Dr. Chilton defended genetically modified foods, pointing out that plant engineering has been happening in nature for centuries.
“If people understood the science, I think the worry would go away,” she said in a 2016 interview with the alumni association of the University of Illinois, where she earned her bachelor’s degree in chemistry in 1960 and her Ph.D. in 1967.
After completing postdoctoral research in bacterial genetics at the University of Washington in Seattle, Dr. Chilton joined the faculty there in 1970, one of only two women in the Department of Microbiology and Immunology. She worked with a soil microbe called Agrobacterium tumefaciens, a sort of Uber driver for gene transport. Over time, it will become the queen of Agrobacterium.
As part of a class assignment in the mid-1970s, a student presented a paper by a Belgian scientist who proposed that Agrobacterium could insert its own DNA into a plant cell, causing plant cancer — tumor-like growths called crown crown disease. Dr. Chilton was skeptical.
“I was there to debunk the whole story,” she said in a 2016 oral history for the Genetic Engineering and Society Center at North Carolina State University.
In the end, she was happy to prove herself wrong.
In 1977, Dr. Chilton and colleagues published a paper in the journal Cell demonstrating that Agrobacterium could transfer a piece of its own DNA into the cells of a tobacco plant. The DNA would then fuse with the plant’s chromosomes, causing the production of tumors and nutrients ensuring the bacteria’s survival. He was a natural genetic engineer.
“We could hardly believe our eyes,” Dr. Chilton wrote in a 2017 biographical essay titled “My Secret Life,” published in The Annual Review of Plant Biology.
The possibilities for manipulating plants were enticing. Dr. Chilton was 38 years old at the time, married with two young sons, and had no path to securing a position at the University of Washington. In 1979, she and her family moved to St. Louis, where she joined the biology faculty at Washington University.
Continuing to work with Agrobacterium, she led a research team that showed it was possible to disarm tumor-causing genes and use the bacteria to transfer foreign genes of their choosing into a plant cell. In 1982, his team, working with Dr. Binns of the University of Pennsylvania, transferred a yeast gene into a tobacco plant and was able to demonstrate that the gene was passed down to the plant’s descendants.
This was indeed the birth of plant genetic engineering technology. This paved the way for the implantation of genes into other crops, including corn, cotton and soybeans, to produce desirable traits, including resistance to pests and herbicides.
This success and similar achievements by a competing company, Monsanto, and Belgian and German scientists were announced at a symposium in Miami in January 1983. Dr. Chilton’s achievements were also recognized three months later in the journal Cell.
“It became pretty clear that this was going to have huge implications on crops, on agriculture,” Dr Binns said.
Mary Dell Matchett II was born February 2, 1939, in Indianapolis and named after her mother, Mary Dell (Hayes) Matchett, who ran the household. (Her first name was hyphenated after a teacher called her Mary, which her mother did not like.) Her father, William E. Matchett, was an insurance executive.
From age 3 until adolescence, she lived primarily with her maternal grandparents in Southern Pines, North Carolina, because an older brother tormented her, she wrote in her autobiographical essay. Her grandmother Henrietta Dell Hayes, who owned a clothing store and kept her own books, was a formative influence on Mary-Dell, her son said, showing her “that women can do things in the world.”
She eventually joined her immediate family, who had moved to the Chicago suburbs and attended high school there. She built a telescope and, in 1956, was one of eight girls among 40 national finalists in a prestigious Westinghouse science competition. She received a National Merit Scholarship to attend the University of Illinois.
In 1966, she married Scott Chilton, who worked as a professor of chemistry, biology and botany during his career. He died in 2004. In addition to her son Mark, she is survived by another son, Andrew, and two grandchildren.
Dr. Chilton left academia in 1983 and returned to North Carolina, helping to establish the research department of what is now Syngenta, a global agribusiness and biotechnology company, where she worked on the genetic engineering of corn and cotton, among other projects.
She admitted to being flattered by the praise for her achievements. “I’m an iconic character,” she joked to the Raleigh News & Observer in 2013.
“You can’t stop me,” she said after being inducted into the National Inventors Hall of Fame in 2015. “When I look for something, I work at it endlessly until I get it.”
