ST. LOUIS — In a nondescript basement lab, jeans-clad engineers clutch blueprints, scrape stepladders across the unfinished floor and chat about the Cardinals as they tighten bolts on a new prototype device. At first glance, it could be any machine shop in the country.
But then you notice the wispy strands of soybean seedlings curling to life, their root tendrils bunched into test tubes lightly packed with soil, and you remember — this place is all about seeds.
Monsanto Co. produces 90 percent of the world’s transgenic crops, using a complex marriage between ancient techniques — cross-breeding different plants to produce a desired trait — and the most modern technologies available, from genomic research to NASA-caliber mechanical engineering.
Originally a chemical company, Monsanto produced some of the world’s most controversial substances — saccharine, DDT, PCBs, Agent Orange — before evolving into the biotech giant it is today. That evolution has been marked by controversy, including lawsuits against farmers, allegations of unfair trade practices, and more. The company produces the herbicide Roundup, and also seeds whose genes have been engineered to survive Roundup's active plant-killing ingredient. Now the vast majority of this country’s soybeans, corn, sugar beets and canola possess those engineered genes.
Behind every single seed is at least a decade of research involving geneticists, engineers and farmers, working to produce a seed that will grow exactly as expected, and in a way nature may not have intended. Here's how it’s done.
Step one: Finding a new trait
Ginny Ursin, head of technology prospecting at Monsanto, has been studying plants most of her life; at age 10, she cobbled together a makeshift greenhouse in the front yard. It was well-built enough that a city building inspector dropped by to inquire about a permit, she recalled. After obtaining her Ph.D in genetics from the University of California-Davis, she studied the biochemical pathways that allow plants to accumulate oil. She has spent more than a decade developing a new omega-3 soybean, which actually produces a precursor fatty acid that our bodies convert into a heart-healthy type of omega-3 — fish oil without the fish. Its history includes Alaskan wildflowers, a type of mold used in Indonesian cooking and years of patient cultivation.To produce a genetically modified organism, you have to identify the trait you want the plant to have, and find out what other organisms already have it. This involves luck as much as careful searching — Monsanto first produced “Roundup Ready” glyphosate-tolerant plants using a gene from bacteria found growing near a Roundup factory. Ursin pored over science texts outlining organisms’ fatty acid compositions, tested hundreds of flowers and fungi, and finally narrowed down the web of life to two fatty-acid-producing enzymes found in primrose flower and a mold called neurospora.
Concocting a transgenic soybean seed also involves testing the plants themselves to find the most worthy subjects. Monsanto invented some cutting-edge technology to help its scientists make that step more efficient.
Step two: Grabbing genes
In the past, studying the genetic code of individual seeds required planting the seed, growing the plants to a certain size, and then clipping a paper-hole-puncher through a leaf to gather a sample. But that’s a time-consuming and resource-heavy process, so it’s easier to study the seeds themselves, explains Kevin Deppermann, head of Monsanto’s automation engineering department. This requires grinding them up, which is also inconvenient, because a ground-up seed can’t be planted. To get around this, Monsanto engineers invented a special chipping device that shaves off just a tiny piece of the seed and grinds it into a powder that can be analyzed with genome-mapping technology. Meanwhile, the viable remainder of the seed is preserved for planting and cultivation.
“Now we know what genes are in the seed before it’s in the ground,” Deppermann said.
It was easy to design a chipper for soybeans, because the seeds are shaped such that they always fall a certain way. But corn kernels are all different, and you don’t want to shave off the wrong part and kill the embryo. Monsanto’s corn chipper uses cameras and object-recognition algorithms to determine how each seed should be aligned for proper chipping. Next-generation chippers for melons and other fruits have a camera that takes 100,000 frames per second — all to help geneticists find new traits even faster.
Step three: “Trait insertion”
Now that you’ve got your genes, the next step is inserting them into the plants. There are a couple ways to do this, including using “gene guns” that literally shoot pieces of DNA. A .22-caliber charge fires a metal particle coated with DNA into plant tissue. Monsanto no longer uses the technique, but it's still widely used among other biotech companies.
For omega-3 soybeans, Ursin and colleagues used a slightly more delicate process, heating soybean seedlings to place them under stress and make them susceptible to a bug called Agrobacterium tumefaciens. The organism specializes in invading plant DNA and tricking it into producing sugars and amino acids that feed the bacteria. Scientists can exploit this Trojan horse ability and insert new proteins into the plant’s chromosomes. The plant recognizes this foreign encoded protein as one of its own, Ursin said.
“This is now in all the plant progenitor cells. The pollen will have that DNA in its genome, so when you have a pollination event and create new seed, that trait is advanced into the next generation,” she said. And there you have it: a first-generation genetically modified plant.
It's also a game of chance — just like with breeding, you never know how the offspring will turn out. Ursin and colleagues produced large sets of modified seedlings to make sure the new genes ended up in the right spot on the genome, because if they don’t, the plant could suffer myriad side effects that would make it unsuitable for sale (at a premium price) to farmers. The next step: finding the best candidates.single page
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