Variations in the gene, known as CHI3L1, can either promote or protect against asthma, they wrote in a report in the New England Journal of Medicine.
"There is a good deal more we need to find out about this connection, but now we know where to look," Carole Ober, a professor of human genetics at the University of Chicago who led the study, said in a statement.
Her team studied a group of Hutterites, members of an Anabaptist group who follow an agrarian lifestyle. They intermarry and thus have a clear genetic lineage that is easy to follow. They also suffer from high rates of asthma.
The researchers homed in on a gene called CHI3L1, which affects levels of a specific compound linked with susceptibility to asthma, overreaction of the bronchial tubes and damaged lung function.
One version raises levels of this compound, YKL-40, while another lowers it and protects people against asthma, they found.
"This is also the most significant genetic discovery based on our years of gathering data on asthma in the Hutterites," Ober said.
"This is a group with enormous potential to advance our understanding of the genetic underpinnings of disease. We now have a remarkable collection of data, which we expect will lead us to many more insights."
The Hutterites came to the United States in 1874 and settled in small communal farming colonies in what is now South Dakota.
The findings could help lead to new drugs to treat asthma, which affects more than 22 million people in the United States alone, the researchers said.
For some people, if you block YKL-40 you might dramatically reduce the severity of the disease," Ober said.
One of the researchers, Dr. Jack Elias of Yale University in Connecticut, has licensed a patent for a drug regulating YKL-40 to MedImmune, a biotechnology company owned by AstraZenec.
Last Mod: 10 Nisan 2008, 14:32