WASHINGTON -- Using genetics, scientists have been able to dig up the dirt on why homegrown tomatoes taste so much sweeter than the ones in the supermarket.

Researchers found a genetic switch responsible for some of the sugar production within a tomato. A new study in Friday's edition of Science found that the common type of tomato bred for firmness and good shipping also inadvertently turns off the sugar-producing switch. That makes it less sweet and blander than garden varieties.

University of California Davis plant scientist Ann Powell said knowing the genetics behind the sugar-making could lead someday to development of sweeter tomatoes that also travel well.