title: Socio-economic status is associated with epigenetic differences in the pSoBid cohort.
abstract: BACKGROUND
  Epigenetic programming and epigenetic mechanisms driven by environmental factors are thought to play an important role in human health and ageing. Global DNA methylation has been postulated as an epigenetic marker for epidemiological studies as it is reflective of changes in gene expression linked to disease. How epigenetic mechanisms are affected by psychological, sociological and biological determinants of health still remains unclear. The aim of this study was to investigate the relationship between socio-economic and lifestyle factors and epigenetic status, as measured by global DNA methylation content, in the pSoBid cohort, which is characterized by an extreme socio-economic and health gradient.
  
  
  METHODS
  DNA was extracted from peripheral blood leukocytes using the Maxwell® 16 System and Maxwell® 16 Blood DNA Purification kit (Promega, UK). Global DNA methylation was assessed using Methylamp™ Global DNA Methylation Quantification Ultra kit (Epigentek, USA). Associations between global DNA methylation and socio-economic and lifestyle factors were investigated in linear regression models.
  
  
  RESULTS
  Global DNA hypomethylation was observed in the most socio-economically deprived subjects. Job status demonstrated a similar relationship, with manual workers having 24% lower DNA methylation content than non-manual. Additionally, associations were found between global DNA methylation content and biomarkers of cardiovascular disease (CVD) and inflammation, including fibrinogen and interleukin-6 (IL-6), after adjustment for socio-economic factors.
  
  
  CONCLUSIONS
  This study has indicated an association between epigenetic status and socio-economic status (SES). This relationship has direct implications for population health and is reflected in further associations between global DNA methylation content and emerging biomarkers of CVD.
authors.affiliation: Institute of Cancer Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK.
authors.forename: Dagmara
authors.initials: D
authors.lastname: McGuinness
authors.forename: Liane M
authors.initials: LM
authors.lastname: McGlynn
authors.forename: Paul C D
authors.initials: PC
authors.lastname: Johnson
authors.forename: Alan
authors.initials: A
authors.lastname: MacIntyre
authors.forename: G David
authors.initials: GD
authors.lastname: Batty
authors.forename: Harry
authors.initials: H
authors.lastname: Burns
authors.forename: Jonathan
authors.initials: J
authors.lastname: Cavanagh
authors.forename: Kevin A
authors.initials: KA
authors.lastname: Deans
authors.forename: Ian
authors.initials: I
authors.lastname: Ford
authors.forename: Alex
authors.initials: A
authors.lastname: McConnachie
authors.forename: Agnes
authors.initials: A
authors.lastname: McGinty
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: McLean
authors.forename: Keith
authors.initials: K
authors.lastname: Millar
authors.forename: Chris J
authors.initials: CJ
authors.lastname: Packard
authors.forename: Naveed A
authors.initials: NA
authors.lastname: Sattar
authors.forename: Carol
authors.initials: C
authors.lastname: Tannahill
authors.forename: Yoga N
authors.initials: YN
authors.lastname: Velupillai
authors.forename: Paul G
authors.initials: PG
authors.lastname: Shiels
mesh_terms: D000328:Adult; D015331:Cohort Studies; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D005260:Female; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012923:Social Class