There are growth industries, and then there are sexy growth industries.

Auto repair, day care and home health care are on the list of industries that the U.S. Labor Department thinks will experience the fastest growth this decade. They'll create jobs because they provide services we all need.

The sexy growth industries aren't about jobs so much. They're about touching millions of lives by creating a new wonder drug or social media site. They measure success by the amount of wealth they create, not the number of people they hire, so they're easily overlooked by job-counting politicians.

And yet, economists say, small cutting-edge firms will determine whether a region's economy grows or stagnates. The absence of such firms is often blamed for St. Louis' longtime status as an economic laggard.

"We can only grow so many hospital jobs in a region because there are only so many sick people," says Jack Strauss, professor of economics at St. Louis University. "But biotechnology, firms that employ scientists to develop new products, that's where our future looks rather bright."

Some St. Louisans might be surprised to hear just how bright. A recent study called the National Cluster Mapping Project, overseen by Michael Porter of Harvard Business School, ranks St. Louis' biopharmaceutical cluster as the sixth-biggest in the nation, ahead of such areas as Boston, Cleveland and San Diego.

It's a tiny industry jobs-wise: Biopharmaceutical firms employed 5,590 people here in 2009, or 0.4 percent of all metropolitan area workers. Add the smaller medical devices cluster, with 2,673 jobs, and you still have fewer than 1 percent of St. Louisans working on the cutting edge of medicine.

Fixating on jobs, though, understates these firms' importance. "The industry helps drive prosperity for the region," says Donn Rubin, president of industry group BioSTL. "It supports related industries as well. ... and it's a high-growth area where substantial wealth can be built that is invested back into the community in terms of philanthropy and new business ventures."

Indeed, the possibility of getting rich is what makes these industries sexy. The success of firms like Facebook, which may be valued as high as $100 billion in its upcoming stock offering, has created an entrepreneurial boom in the information-technology sector, including in St. Louis.

In Porter's study, information technology isn't a strength for St. Louis. He ranks the local IT cluster No. 60 in the nation, with just 2,987 workers.

Far more tech jobs here are housed inside big employers like Mastercard and Enterprise Rent-a-Car. They depend on being able to hire a steady stream of skilled workers, and a healthy startup culture helps draw those workers to town.

Recently, about a dozen small tech companies have moved into the new T-Rex workspace downtown, and the Information Technology Entrepreneur network estimates that at least 600 people work for early-stage technology firms here.

Our big, established companies watch the little ones with interest, and not because they see competition. Rather, they see an advertisement of St. Louis as a great place to build a technology career.

"I am a huge believer for us to have a vibrant IT ecosystem," says Mark Showers, chief information officer at Reinsurance Group of America, based in Chesterfield. "Having that (startup) outlet brings more people here, and keeps the ones we graduate here."

With luck, a few of our cutting-edge companies will become big job creators someday. Until then, we must learn to value them in other ways.