Genetically modified crops reached 9 percent of global primary crop production in 2007, bringing the total GM land area up to 114.3 million hectares, according to Worldwatch Institute estimates published in the latest Vital Signs Update. The United States continues to be the global leader in production, accounting for half of all GM crop area.

GM production has been on the rise since the crops were first introduced more than a decade ago, and it now includes 23 countries. But controversy over the benefits of genetic modification continues, including questions about the technology’s ability to deliver on promises of enhanced yields and nutrition.

“GM crops are definitely not a silver bullet,” said Alice McKeown, a researcher for the Worldwatch Institute. “They sound good on paper, but we have yet to see glowing results.”

Even as GM crop area expands, tensions are building. The European Union is expected to offer new guidance on the crops by the end of the year. Meanwhile, a new scientific study funded by the Austrian government suggests that a popular variety of GM corn reduces fertility in mice, raising questions about the technology’s safety.

“There are still many unanswered questions about GM crops,” said McKeown. “But the good news is that we have solutions to food security and other problems available today that we know work and are safe for humans and the environment, including organic farming.”

So what do you think? People have been “genetically modifying” plants and animals for thousands of years. You think dogs got the way they are today without a dedicated program of selected breeding? How about wheat and corn, 10,000 years ago wheat was a spindly grass, and corn didn’t look anything like it does today. Humans have been slowly modifying things for thousands of years, now that we can do so at a cellular level does that change anything? Are we being overly cautious, or are people right to fear what could happen? Let your voice be known in the comment section.