Mucus associated gene tied to lung disease

Carrying a variant form of a gene might add to a person’s risk of increasing a devastating lung disease called pulmonary fibrosis. The variation induces the body to overproduce mucus in the lungs, researchers statement in the April 21 New England Journal of Medicine. Pulmonary fibrosis, a scarring of the lungs, is a rare but lethal condition that presently affect about 100,000 people in the United States. Although the cause of pulmonary fibrosis is unclear, scientists suspect a grouping of genetic factors and environmental irritants such as exposure to cigarette smoke, asbestos fibers or silica dust.

There is no cure, and survival after study is often only three to five years, says James Kiley, a pulmonary physiologist at the National Heart, Lung and Blood Institute in Bethesda, Md., who was not part of the new study. The findings might point to one of the root reason of pulmonary fibrosis, he says, “and may guide to something to prevent or manage this disease a bit better.” Mucus defends air passages from foreign pathogens and pollutants. But too much mucus in the lungs can become sticky and hard to clear, growing susceptibility to infection and chronic inflammation. The delicate balance between maintain a protective mucus coating and mucus overproduction is distress in certain lung diseases.

In the new study, David Schwartz, a physician and immunologist at the University of Colorado School of Medicine and National Jewish Health in Denver, and his colleagues experienced the genes of hundreds of people with fit lungs and with pulmonary fibrosis. The patients included some who had family members with the disease and others who did not, in what are recognized as sporadic cases. The scientists inspect genes that encode mucin proteins, the chief components of mucus. A alternative form of the mucin-5B gene, called MUC5B, stood out, viewing up in 59 percent of people with familial forms of pulmonary fibrosis and 67 percent of those with irregular pulmonary fibrosis, but in only 19 percent of the healthy group.