BEIJING, Oct. 8 — An ordinary-looking white flower from Japan may carry the longest genome ever discovered, a new study suggested Thursday.

The Paris japonica, a 12-inch (30-centimeter) flower native to Japan, has a genetic code 50 times long as that of a human being, researchers at London’s Kew Gardens discovered.

If laid end-to-end, this flower’s genome would stretch to more than 300 feet (about 91 meters), the researchers said.

A genome is the full complement of an organism’s DNA, complex molecules that direct the formation and function of all living organisms.

The size of an organism’s genome is typically measured by the number of base pairs — the building blocks of DNA.

The human genome has about 3 million bases and measures about 6 feet (1.8 meters) in length. The known organism with the second longest genome is the marbled lungfish, which has 130 million bases. And the newly discovered flower turns out to have 150 million bases.

However, researchers said bigger genomes don’t necessarily mean a more complex organism.

While genes are generally supposed to correspond to some traits in organisms, many genes don’t appear to correspond to anything. 

On Xinhua Web site: http://news.xinhuanet.com/english2010/sci/2010-10/08/c_13546906.htm