title: Exposure to airborne particulate matter is associated with methylation pattern in the asthma pathway.
abstract: BACKGROUND
  Asthma exacerbation and other respiratory symptoms are associated with exposure to air pollution. Since environment affects gene methylation, it is hypothesized that asthmatic responses to pollution are mediated through methylation.
  
  
  METHODS
  We study the possibility that airborne particulate matter affects gene methylation in the asthma pathway. We measured methylation array data in clinic visits of 141 subjects from the Normative Aging Study. Black carbon and sulfate measures from a central monitoring site were recorded and 30-day averages were calculated for each clinic visit. Gene-specific methylation scores were calculated for the genes in the asthma pathway, and the association between the methylation in the asthma pathway and the pollution measures was analyzed using sparse Canonical Correlation Analysis.
  
  
  RESULTS
  The analysis found that exposures to black carbon and sulfate were significantly associated with the methylation pattern in the asthma pathway (p-values 0.05 and 0.02, accordingly). Specific genes that contributed to this association were identified.
  
  
  CONCLUSIONS
  These results suggest that the effect of air pollution on asthmatic and respiratory responses may be mediated through gene methylation.
authors.affiliation: Department of Biostatistics, Harvard School of Public Health, MA, USA. tsofer@hsph.harvard.edu
authors.forename: Tamar
authors.initials: T
authors.lastname: Sofer
authors.forename: Andrea
authors.initials: A
authors.lastname: Baccarelli
authors.forename: Laura
authors.initials: L
authors.lastname: Cantone
authors.forename: Brent
authors.initials: B
authors.lastname: Coull
authors.forename: Arnab
authors.initials: A
authors.lastname: Maity
authors.forename: Xihong
authors.initials: X
authors.lastname: Lin
authors.forename: Joel
authors.initials: J
authors.lastname: Schwartz
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000397:Air Pollution; D001249:Asthma / Q000139:chemically induced / Q000235:genetics* / Q000473:pathology; D002244:Carbon / Q000633:toxicity; D019175:DNA Methylation / Q000187:drug effects*; D044127:Epigenesis, Genetic / Q000187:drug effects; D006801:Humans; D008297:Male; D053858:Metabolic Networks and Pathways / Q000235:genetics; D008875:Middle Aged; D052638:Particulate Matter / Q000633:toxicity*; D011401:Promoter Regions, Genetic; D013431:Sulfates / Q000633:toxicity
chemical_list: D052638:Particulate Matter; D013431:Sulfates; D002244:Carbon