As you probably know, if you've been reading the news or this blog, rice farmers have been scrambling to find seed that's not contaminated with traces of genetically engineered, herbicide-tolerant rice. (The Washington Post looked at the issue Sunday).

There's a curious fact about the current debacle that you probably haven't heard, though, perhaps because journalists don't want to confuse their readers. You know that popular "conventional" variety in which traces of genetic engineering were most recently found? Clearfield 131? Well, it's also a herbicide-tolerant line of rice. It contains a genetic mutation that allows it to tolerate doses of certain chemical herbicides. Scientists created that genetic change by soaking rice in mutation-inducing chemicals. Similar "Clearfield" varieties have been on the market for years, and nobody outside the rice industry paid much attention.

There's really no difference in the potential risks posed by these two kinds of herbicide-tolerance -- one created through genetic engineering and one created by mutation-causing chemicals. So why is one kind exempt from public scrutiny and government regulation, while the other kind sets off trade embargoes? Probably because genetic engineering, unlike chemical mutagenesis, arrived on the scene full of hype and hubris, promising a new creation. Those grand ambitions, as much as anything, provoked the anti-GMO backlash.

- Dan Charles