BEIJING, Jan. 12 -- Researchers at Fudan University have successfully raised genetically modified fish that can detect estrogen pollution in lakes and rivers, showing environmental officials what waterways need to be treated for the substance, which is linked to infertility.
Song Houyan and Zhong Tao, two professors at Fudan's molecular medicine lab, spent three years cloning estrogen-sensitive genes and injecting them into the fertile eggs of zebrafish.
The modified fish turn green if they are placed into water that is polluted by estrogen, Fudan officials said.
"The new type of fish is able to indicate aquatic environmental estrogen pollutants in a direct, acute and convenient way," said Sun Guogen, a spokesperson for Fudan's medical school.
Widely found in water, soil and even food, environmental estrogen poses a great threat to the reproductive abilities of humans and animals, researchers said, noting even a tiny level of estrogen can leave men infertile.
Previous studies suggest average male semen levels around the world have dropped by 40 percent over the past 50 years.
Environmental estrogen is a direct cause of an increase in infertility and congenitally deformed babies in recent years, Sun said.
He and his team have received a national patent for their research, and are currently applying for a patent on a device that automatically raises modified zebrafish.
(Source: Shanghai Daily)