The same genetic mutation that is currently known as a marker of asthma severity might also play a role in causing the disease, according to a recent study from the Yale School of Medicine and the University of Chicago.

Researchers found that one mutation of the YKL-40 gene correlated with a diagnosis of asthma and with impaired lung function. This suggests that increased levels of YKL-40 are part of the fundamental path that leads to asthma.

The study involved 632 people from South Dakota who were genetically homogenous. Identifying genetic links to disease can be easier in a genetically homogenous population.

“In this study we found that a mutation in the YKL-40 gene is associated with YKL-40 levels in the blood, a diagnosis of asthma, and impaired lung function,” says Geoffrey Chupp, MD, associate professor of medicine at Yale, and senior author of the study. “Ultimately, blocking the effects of YKL-40 may prove to be a novel and effective way to treat asthma.”

The study was published in the April 2 edition of the New England Journal of Medicine.