title: Nasal cell DNA methylation, inflammation, lung function and wheezing in children with asthma.
abstract: OBJECTIVE
  DNA methylation is increasingly proposed as a mechanism for underlying asthma-related inflammation. However, epigenetic studies are constrained by uncertainties on whether samples that can be easily collected in human individuals can provide informative results.
  
  
  METHODS
  Two nasal cell DNA samples were collected on different days by nasal brushings from 35 asthmatic children aged between 8 and 11 years old. We correlated DNA methylation of IL-6, iNOS, Alu and LINE-1 with fractional exhaled nitric oxide, forced expiratory volume in 1 s and wheezing.
  
  
  RESULTS
  Fractional exhaled nitric oxide increased in association with lower promoter methylation of both IL-6 (+29.0%; p = 0.004) and iNOS (+41.0%; p = 0.002). Lower IL-6 methylation was nonsignificantly associated with wheezing during the week of the study (odds ratio = 2.3; p = 0.063).
  
  
  CONCLUSIONS
  Our findings support the use of nasal cell DNA for human epigenetic studies of asthma.
authors.affiliation: Exposure Epidemiology & Risk Program, Harvard School of Public Health, Boston, MA 02215, USA. abaccare@hsph.harvard.edu
authors.forename: Andrea
authors.initials: A
authors.lastname: Baccarelli
authors.forename: Franca
authors.initials: F
authors.lastname: Rusconi
authors.forename: Valentina
authors.initials: V
authors.lastname: Bollati
authors.forename: Dolores
authors.initials: D
authors.lastname: Catelan
authors.forename: Gabriele
authors.initials: G
authors.lastname: Accetta
authors.forename: Lifang
authors.initials: L
authors.lastname: Hou
authors.forename: Fabio
authors.initials: F
authors.lastname: Barbone
authors.forename: Pier Alberto
authors.initials: PA
authors.lastname: Bertazzi
authors.forename: Annibale
authors.initials: A
authors.lastname: Biggeri
mesh_terms: D020087:Alu Elements / Q000235:genetics; D001249:Asthma / Q000150:complications / Q000235:genetics* / Q000378:metabolism; D002648:Child; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D005260:Female; D006801:Humans; D007249:Inflammation / Q000209:etiology / Q000235:genetics*; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism; D020084:Long Interspersed Nucleotide Elements / Q000235:genetics; D008168:Lung / Q000503:physiopathology*; D008297:Male; D009297:Nasal Mucosa / Q000166:cytology / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D012135:Respiratory Sounds / Q000209:etiology / Q000235:genetics*
chemical_list: D015850:Interleukin-6; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II