Doane Chilcoat ’93: The Pivot From Crops to COVID Tests

What does agricultural science have to do with pandemic public health?

That’s what Doane Chilcoat ’93 found himself asking in January 2020, as news of COVID-19 outbreaks abroad began to reach him.

As it turns out, the link between the two lay in Chilcoat’s area of expertise: molecular genetics.

A Grinnell biology graduate who received his Ph.D. in molecular genetics and cell biology at the University of Chicago, Chilcoat was leading a large research and development group at Corteva Agriscience in Johnston, Iowa. There, he oversaw development of innovative laboratory and greenhouse techniques for developing Corteva’s seeds and crop protection products.

Agricultural science relies on molecular genetics, Chilcoat explains. From genetically modifying organisms for climate resilience to developing herbicides that selectively target weeds, an understanding of organisms’ genomes is essential.

How does molecular genetics relate to a highly contagious respiratory virus in humans? Well, Chilcoat explains, “Genetic screening is pretty much the same in humans as it is in plants.”

A Critical Connection

In both biological kingdoms, genetic screening relies on technology known as PCR — polymerase chain reaction. Ten years ago, most non-scientists hadn’t heard of PCR. Now, the term is familiar to most who have taken a COVID-19 test.

Invented in the 1980s, PCR rapidly copies a DNA sample, allowing scientists to amplify a single piece of DNA so that it can be detected and studied in detail.

If you traveled early in the pandemic, you’ve likely taken a PCR test. Unlike the rapid antigen tests that provide results in 15 minutes, it usually takes at least a day to get the results of a PCR test. Why? Because PCR samples must be sent to a laboratory with technicians and equipment dedicated to conducting the reaction.

At the outset of the pandemic, Iowa’s PCR testing capacity was inadequate to effectively track and contain the COVID-19 virus. Hospitals and laboratories were overwhelmed. The demand for PCR testing was far greater than the supply.

Yet PCR was nothing new to the scientists at Corteva. “The sort of assays that were being done for COVID testing were the same tests that one of the groups I managed at Corteva was doing at an extremely large scale — for plant genomics,” Chilcoat explains. “We’re talking millions of tests a month.”

He and his colleagues wondered: What if Corteva’s expertise in large-scale genetic screening could help meet the demand for SARS-CoV-2 testing? Corteva could be key to a faster, larger testing system in the state.

Scientists at Corteva began reaching out to contacts in Iowa government, ultimately making a serendipitous connection with the CEO of MercyOne, one of Iowa’s largest hospital networks. Without enough tests for patients, MercyOne hospitals were cancelling elective surgeries. They could benefit from Corteva’s help. And, as it turned out, Corteva needed their help too.

“MercyOne lent a healthcare expertise that helped us move past barriers we hadn’t known how to face,” Chilcoat says. “We weren’t equipped to adhere to HIPAA regulations for handling sensitive patient data.”

Thus began Corteva’s partnership with MercyOne. Corteva would divert equipment and employees to provide SARS-CoV-2 PCR testing. The healthcare company would help them handle patient information.

In just 15 days, Chilcoat oversaw the conversion of equipment rooms to meet biohazard 2 standards. His team applied for expedited federal Clinical Laboratory Improvement Amendments (CLIA) certification. And they proved that they could generate consistent and accurate results for COVID-19 tests.

Working Smarter

In April 2020, the Corteva team began to provide rapid, low-cost COVID-19 testing to MercyOne facilities. They immediately encountered a shortage of their testing materials.

Chilcoat’s team pivoted rapidly, replacing the testing materials with custom reagents from Integrated DNA Technologies in Coralville, Iowa. They also switched from a nasal swab to a saliva collection tube — one of the first labs in the nation to do saliva-based COVID-19 testing at scale.

What came next was even more unprecedented than an agriscience company doing healthcare: the Bill and Melinda Gates Foundation contacted the Corteva team.

The foundation wanted to support programs that used automation and robotics to test at a high scale, Chilcoat says. Why Corteva? Well, Corteva had previously worked with biotechnology companies to develop automated machinery for ultra-high volumes of genome testing. The Gates Foundation wanted to help the company employ those robots for COVID-19 PCR testing.

“The volume of molecular testing in agriculture biotech industry is greater than that in healthcare, historically,” Chilcoat explains. “So Corteva was more prepared for the massive scale of genetic testing that a pandemic response demanded.”

With $10 million from the Gates Foundation, Chilcoat drastically increased the already large scale of Corteva’s testing. “At this point, we basically reinvented every step of the process,” he says.

Corteva developed a much smaller, highly optimized reaction. It used fewer reagents, smaller quantities, and even less time. They worked with a laboratory supplies provider to invent a new collection device — a tube with a short swab that could preserve samples without transport solution. The tube also contained a smaller, hidden cap, which could be robotically removed to allow reagents to be added directly to the sample. (You can watch a video of this entire process on Corteva’s YouTube channel).

The new process was faster and cheaper. “When we built our own test, we were averaging a total cost of about $1,” says Chilcoat. Reagents for tests at other labs cost $25 or $50.

With an affordable, optimized testing protocol, Corteva began expanding its testing services.  They used this technology with the Broadlawns Hospital in Des Moines, the Northwell Health in New York City, and even the National Health Service in Great Britain. And as college campuses in Iowa fought to safely reopen, Corteva tests enabled COVID-19 surveillance. One of those colleges? Grinnell College.

Corteva testing allowed small cohorts of Grinnell students to return to campus for months at a time, offering some semblance of normalcy for students living through a far from typical college experience.

Leaving a Legacy

In May 2021, over a year after Corteva developed its first COVID test, the company discontinued its testing.

Affordable at-home tests and decreased demand for PCR tests signaled it was time for the company to return to its primary mission after more than a year of serving community partners. An article on the company’s webpage announced the program’s end. Since April 2020, the page reads, “Corteva has analyzed more than a quarter million polymerase chain reaction (PCR) tests in Iowa.”

Chilcoat is grateful that Corteva could help address the urgent community need during the pandemic. “It wasn’t the industry that Corteva wanted to be in, but we were positioned to help. So, we did.”

Not long after the end of the testing program, Chilcoat, too, moved on from Corteva. He’s now the vice president of technology and research operations at Design Therapeutics, a biotechnology company in San Diego, California, creating small molecule drugs to treat serious genetic diseases. He returned to Grinnell last week for his 30-year class reunion.