RWP was born in Manchester, in the north of England, in the late 1950s, so he is very old. He really liked the north of England, which by 1965 was hip and had three TV channels, and where he went to a coed school. His parents, for reasons best known to themselves, then yanked him away, to Belfast and then Dublin, which had one TV channel that started up at 6 pm with the Angelus (Catholic call to prayer). He also had to go to an all boys school, where he realized he really missed girls. This probably let him focus on schoolwork, though, and at age 19, after he had finished college, he set off for America, where he still resides. He has a bachelors degree in biochemistry and a Ph.D. from Harvard in biophysics, and has lived also in Mainz, Germany, Setauket NY, and Richland WA. He currently divides his time between Nebraska, Rosslyn VA, and Florida.

Wednesday, September 3, 2014

Chuck Hassebrook's Record: Opposing Biotech, part 1

While our local left-leaning media has been busy trying to pin Pete Ricketts to everything the Platte Institute has ever published, there has been remarkably little analysis of his Democrat opponent's record as an environmental activist and as a member of the Nebraska Board of Regents. Part of this is undoubtedly bias; after all, one of the state's two major newspapers is owned by heavy Hassebrook financial backer Warren Buffett. But I think part of it is a result of the average political reporter's complete ignorance about science. If you have no idea what genetic modification is or how it's done, what it's used for in contemporary agriculture, and the history of its research, development and commercial implementation, how can you write a piece about it? To remedy this, I'm going to be writing a series of posts explaining GM and its enormous economic and other benefits to Nebraska, and then describing the extreme and sustained nature of Hassebrook's opposition to GM agriculture. At the end, I hope at least ask yourself how this fringe anvironmental activist could propose to govern an agricultural state like ours.

Genetic modification, succinctly, is the introduction of genes from foreign organisms into the genome of one's organism of choice. This has been happening slowly and quietly for billions of years; when a virus infects a cell, it occasionally incorporates some of the cell's DNA into its own genome. The virus's descendents can then go on to infect and transform other cells, sometimes modifying their genomes. In the early 1980s, we learned to do this much faster and in a directed way. Agrobacterium, a genus of plant bacteria, naturally transfers DNA between it and its hosts, via small extra 'chromosome-like' piece of DNA called plasmids. So a scientist can choose a gene from one organism, synthesize a plasmid containing the gene, infect Agrobacterium with it, infect a plant with the Agrobacterium, and screen the cells or offspring of the plant for ones that have successfully incorporated the gene. You can now buy kits to do this; it's so easy I've done it myself (I genetically engineered a bacterium to overproduce a plant protein called azurin). If Agrobacterium won't infect the plant (it doesn't infect corn) we can use something called a gene-gun to fire bits of DNA through the plant cell wall, again screening for descendants that have incorporated the gene into their own genomes.

Aside from a commercially unsuccessful attempt to genetically engineer frost-resistant tomatoes, the earliest atttempts to genetically engineer crops involved trying to introduce herbicide resistance (remember that term). The most successful of these GM-crops have been 'Roundup-resistant'. These are based on a very simple but elegant strategy of introducing a gene, already native to Agrobacterium, for the enzyme 5-enolpyruvylshikimate-3-phosphate synthase (or EPSP synthase). EPSP synthase is vital to all plants, because it's used in the pathway to make the essential aromatic amino acids phenylalanine, tyrosine, and tryptophan. Animals, however, don't need it, because we can't make aromatic amino acids, and have to get them in our diet. So if we can block, EPSP synthase, we can kill plants, but leave animals unharmed. And this is what Roundup, technically known as glyphosate and even more technically as N-(phosphonomethyl)glycine) does. It diffuses into the active site of the EPSP synthase enzyme, and sits there, tightly bound, preventing the enzyme from doing its job. Glyphosate is an extremely simple molecule, and is almost completely nontoxic to humans and other animals (naturally enough, since we don't have its target enzyme).

So where does genetic engineering come in? Well, Agrobacterium also makes its own aromatic amino acids, and so also has EPSP synthase. But Agrobacterium EPSP-synthase is structurally different from the plant enzyme, and is not blocked by glyphosate. So all you have to do is replace the plant enzyme with the bacterial enzyme, or even more easily, just give the plant the bacterial enzyme naturally, with a promoter that will cause it to overexpress, and the plant will still be able to make its essential amino-acids and will be resistant to the herbicide.

So now a farmer can plant his corn and soybeans on a field already cleared by glyphosate. He can even spray glyphosate on the field while his crops are growing, killing weeds but not his crops. The result is higher yield, and no need to use selective herbicides like atrazine, which are far more toxic to humans.

How could anyone oppose that? Well, as we'll see in the next post, Chuck Hassebrook did.

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