Asthma severity gene is identified

NEW HAVEN, Conn., Sep 20, 2005 (United Press International via COMTEX) -- Yale School of Medicine researchers in New Haven, Conn., say they have identified a gene that controls the clinical severity of asthma.

"Asthma patients who have high production variants of the macrophage migration inhibitory factor gene are more likely to have severe disease," said Dr. Richard Bucala, an internal medicine professor and senior author of the study.

Bucala and colleagues in Dublin, Ireland, included experiments in mice that are resistant to developing asthma because they lack the MIF gene, and an examination of a human population in Dublin chosen for their similar ethnic and geographic identity.

When challenged with a trigger for their asthma attack, the genetically deficient mice had less pulmonary inflammation and lower airway hyper-responsiveness than genetically matched, wild-type control mice.

Similarly, in an analysis of 151 Caucasian patients with mild, moderate and severe asthma, there was a significant association between mild asthma and the low expression of MIF.

The study is presented in this week's Proceedings of the National Academy of Sciences.