title: Ancestral haplotype 8.1 and lung disease severity in European cystic fibrosis patients.
abstract: BACKGROUND
  The clinical course of cystic fibrosis (CF) lung disease varies between patients bearing identical CFTR mutations. This suggests that additional genetic modifiers may contribute to the pulmonary phenotype. The highly conserved ancestral haplotype 8.1 (8.1AH), carried by up to one quarter of Caucasians, comprises linked gene polymorphisms on chromosome 6 that play a key role in the inflammatory response: LTA +252A/G; TNF -308G/A, HSP70-2 +1267A/G and RAGE -429T/C. As inflammation is a key component inducing CF lung damage, we investigated whether the 8.1AH represents a lung function modifier in CF.
  
  
  METHODS
  We analyzed the lung function of 404 European CF patients from France (n=230), Germany (n=95) and UK (n=79). FEV(1) differences between 8.1AH carriers and non-carriers were calculated in each country and pooled using a random effects model.
  
  
  RESULTS
  The frequency of 8.1AH carriers was similar between French (22%), German (29%) and UK (27%) patients. We found that 8.1AH carriers had significantly lower FEV(1), adjusted for age classes and countries (P<0.04, mean FEV(1) difference -6.4% CI95% [-12.4%, -0.5%]). No difference was observed with respect to BMI Z-scores and chronic colonization with P. aeruginosa.
  
  
  CONCLUSIONS
  These findings support the concept that 8.1AH is an important genetic modifier of lung disease in CF. To conclude, multiple linked genes outside the CF locus might explain some of the variability in lung phenotype.
authors: AP-HP, Hôpital Trousseau, Pediatric Pulmonary Department, Inserm U938, Paris, France. harriet.corvol@trs.aphp.fr
authors: Harriet
authors: H
authors: Corvol
authors: Julie
authors: J
authors: Beucher
authors: Pierre-Yves
authors: PY
authors: Boëlle
authors: Pierre-François
authors: PF
authors: Busson
authors: Céline
authors: C
authors: Muselet-Charlier
authors: Annick
authors: A
authors: Clement
authors: Felix
authors: F
authors: Ratjen
authors: Hartmut
authors: H
authors: Grasemann
authors: Judith
authors: J
authors: Laki
authors: Colin N A
authors: CN
authors: Palmer
authors: J Stuart
authors: JS
authors: Elborn
authors: Anil
authors: A
authors: Mehta
mesh_terms: D000293:Adolescent; D002648:Child; D002896:Chromosomes, Human, Pair 6 / Q000235:genetics; D003550:Cystic Fibrosis / Q000235:genetics* / Q000503:physiopathology*; D005260:Female; D005541:Forced Expiratory Volume; D060045:Genes, Modifier; D020022:Genetic Predisposition to Disease / Q000235:genetics; D006239:Haplotypes; D006801:Humans; D007249:Inflammation / Q000235:genetics; D008168:Lung / Q000503:physiopathology*; D008285:Major Histocompatibility Complex / Q000235:genetics*; D008297:Male; D020412:Multifactorial Inheritance; D010641:Phenotype; D011110:Polymorphism, Genetic; D044465:White People / Q000235:genetics*