CGS-authored

Here's something that might sound strange: There are companies now that print and sell DNA.

This trend — which uses the term "print" in the sense of making a bunch of copies speedily — is making particular stretches of DNA much cheaper and easier to obtain than ever before. That excites many scientists who are keen to use these tailored strings of genetic instructions to do all sorts of things, ranging from finding new medical treatments to genetically engineering better crops.

"So much good can be done," says Austen Heinz, CEO of Cambrian Genomics in San Francisco, one of the companies selling these stretches of DNA.

But some of the ways Heinz and others talk about the possible uses of the technology also worries some people who are keeping tabs on the trend.

"I have significant concerns," says Marcy Darnovsky, who directs the Center for Genetics and Society, a genetics watchdog group.

A number of companies have been taking advantage of several recent advances in technology to produce DNA quickly and cheaply. Heinz says his company has made the...