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Geneticist Norman Ellstrand goes with the flow

AAAS member Norman Ellstrand studies the gene flow of wild and cultivated plant populations. (Photo: Rebecca Fairley Raney)

In the early 1980s, as he cultivated and studied vast numbers of radishes from an experimental field, Norman Ellstrand was faced with a significant problem: He was breeding babies with impossible fathers.

As he studied the genes of the babies, he found that as many as 10 percent turned up with DNA that couldn't have come from his field.

At that point, Ellstrand, who was trained in evolutionary biology, had spent a few years doing applied research at the University of California at Riverside. He had more publications on the cherimoya, the third most important fruit in California, than anyone else.

But this problem with the radish babies was a dicey one. He and his students examined every possible explanation. Were their methods unsound? Were the samples corrupted? They weren't. Ultimately, they found that the only possible explanation was that the fathers came from outside the field. Wild radishes were breeding with his crop.

On its face, this discovery may not sound that shocking. But at the time, the scientific community generally believed that wild plants don't mate with their cultivated cousins. This was a comfortable belief; the idea that pristine plant populations can be altered by human cultivation is a social and political hot potato.

Colleagues offered friendly warnings.

"One said, 'The companies are going to try to shut you down,' " Ellstrand said. Ultimately, he said, that worry was unfounded. He became a sought-after speaker for companies like Monsanto on the topic of bio-safety.

Ellstrand talks about the 30-year evolution of his research while sitting in a tiny office on the fourth floor of a lumbering faculty office building on the UCR campus. It's not a quiet place. The building vibrates with roar of tall steel freezers standing in the hallway. The freezers are stuffed with leftover DNA from dozens of experiments.

On his office door, a vivid poster proclaims "Transgenes Gone Wild!" Pictured on the poster are four large watermelons, ripe and green and decidedly square in shape. (\They were grown in a box," Ellstrand explains. "Not altered.\")

The poster, he said, is a great example of the brand of silliness subscribed to by people in his field.

Half of the window sill in his office is filled with books about birds. In his early days studying biology, Ellstrand thought he wanted to study birds. But Donald Levine, a mentor in graduate school at the University of Texas, talked him into plants.

"He said, 'They stand in place, so when you come back, the population is still there. They don't bite you. They don't poop on you.' "

He was sold.

After the initial paper on the mating of wild and cultivated radishes in 1985, he continued working in the area of conservation genetics. A couple of years later, he gave a talk called "Long-Distance Romance\" at a conference. His last slide raised the question about what would happen if engineered genes got into wild populations. When the talk ended, an editor at the journal Trends in Ecology and Evolution tracked him down and asked him to pursue that question in greater depth.

"Basically," Ellstrand said, \"it started raining offers after that paper."

In the 30 years since that initial discovery,  Ellstrand found that not only do many cultivated plants breed with wild relatives, but that the babies of those unions can be more robust.

Genes from genetically engineered plants are getting into the wild populations, and genes from the wild populations are getting into cultivated fields. In most cases, these mutations are not important. But it matters when it comes to weeds. As a result, some weeds get bigger, better and harder to kill. One mutation in Europe is causing substantial damage to beet fields.

These discoveries led to a book, \"Dangerous Liaisons? When Cultivated Plants Mate With their Wild Relatives," in 2003. And they led to many awards. There was the Fulbright Fellowship, in 1993. The UCR Dissertation Advisor/Mentoring Award in 2004. The Botanical Society of America's Merit Award, which is the highest award given by the organization. And the 2010 Guggenheim Fellowship, among others.

In 2012, he was selected to give the UCR Faculty Research Lecture.

Decades after that first controversial discovery, he is part of not just a figurative University of California family, but a literal one, as well. His wife, Tracy Kahn, is curator of UCR's Citrus Variety Collection, a 100-year-old station that contains more than 1,000 varieties of citrus trees. Their son, Nathan, is a social scientist at the University of California at Davis.

And Ellstrand continues to get invitations to speak to academic audiences, and to safety groups from corporations concerned about herbicide resistance.

"When I show up at the bio-safety conferences now," he said, \"instead of the pariah, I'm the grand old man."