A gene mutation that makes a tomato uniformly red, favored by farmers as it produces a visually attractive product, stifles genes that would contribute to its taste, scientists said.
The chance mutation discovered by tomato breeders has been deliberately bred into almost all tomatoes for the color it provides.
Researchers writing in the journal Science report the gene that was inactivated by that mutation -- resulting in a brighter uniform color -- plays an important role in producing the sugar and aromas that are central to a flavorful tomato.
The wide adoption of tomatoes with the genetic mutation is "a story of unintended consequences," said study co-author James J. Giovannoni of the United States Department of Agriculture Research Service.
The discovery "is one piece of the puzzle about why the modern tomato stinks," said Harry Klee, a tomato researcher at the University of Florida in Gainesville who was not involved in the research, told The New York Times.
"That mutation has been introduced into almost all modern tomatoes. Now we can say that in trying to make the fruit prettier, they reduced some of the important compounds that are linked to flavor."