title: Severity of cough in idiopathic pulmonary fibrosis is associated with MUC5 B genotype.
abstract: BACKGROUND
  A polymorphism (rs35705950) in the promoter region of the mucin MUC5B is associated with both familial and sporadic forms of idiopathic pulmonary fibrosis. (IPF) We hypothesize that this common MUC5B variant will impact the expression of cough, a frequent disabling symptom seen in subjects with IPF.
  
  
  METHODS
  We genotyped 136 subjects with IPF. All living subjects were provided with a Leicester Cough Questionnaire (LCQ) to measure cough severity. We assessed allele effects of the MUC5B polymorphism on the LCQ scores using SAS General Linear Models (GLM) in the patients with IPF.
  
  
  RESULTS
  In the 68 of the total 136 IPF patients who returned the LCQ, MUC5B minor allele frequency (T) is consistent with prior published studies (31%). We found a significant independent effect of the T allele on the LCQ score (p = 0.002 for subjects with IPF). This effect is independent of other common causes of cough, including gastroesophogeal reflux disease and upper airway cough syndrome.
  
  
  CONCLUSIONS
  Cough severity, a common disabling phenotypic component of IPF, is significantly associated with the presence of the minor allele of a MUC5B promoter polymorphism. This study highlights a possible genetic mechanism for phenotypic heterogeneity in pulmonary fibrosis.
authors.affiliation: Division of Pulmonary Medicine, Department of Internal Medicine, University of Utah School of Medicine, 420 Chipeta Way, Suite 2020, Salt Lake City, UT 84108, USA.
authors.forename: Mary Beth
authors.initials: MB
authors.lastname: Scholand
authors.affiliation: Division of Clinical Epidemiology, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA.
authors.forename: Roger
authors.initials: R
authors.lastname: Wolff
authors.affiliation: Division of Pulmonary Medicine, Department of Internal Medicine, University of Utah School of Medicine, 420 Chipeta Way, Suite 2020, Salt Lake City, UT 84108, USA ; Division of Pulmonary Medicine, Department of Internal Medicine, Intermountain Medical Center, Salt Lake City, Utah, USA.
authors.forename: Peter Fredrick
authors.initials: PF
authors.lastname: Crossno
authors.affiliation: Division of Pulmonary Medicine, Department of Internal Medicine, University of Utah School of Medicine, 420 Chipeta Way, Suite 2020, Salt Lake City, UT 84108, USA.
authors.forename: Krishna
authors.initials: K
authors.lastname: Sundar
authors.affiliation: Division of Pulmonary Medicine, Department of Internal Medicine, University of Utah School of Medicine, 420 Chipeta Way, Suite 2020, Salt Lake City, UT 84108, USA.
authors.forename: Molly
authors.initials: M
authors.lastname: Winegar
authors.affiliation: Division of Pulmonary Medicine, Department of Internal Medicine, University of Utah School of Medicine, 420 Chipeta Way, Suite 2020, Salt Lake City, UT 84108, USA.
authors.forename: Spencer
authors.initials: S
authors.lastname: Whipple
authors.affiliation: Division of Pulmonary Medicine, Department of Internal Medicine, University of Utah School of Medicine, 420 Chipeta Way, Suite 2020, Salt Lake City, UT 84108, USA.
authors.forename: Patrick
authors.initials: P
authors.lastname: Carey
authors.affiliation: University of Montana, Missoula, MT, USA.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Sunchild
authors.affiliation: Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, Utah, USA.
authors.forename: Hilary
authors.initials: H
authors.lastname: Coon