title: Assessment of global DNA methylation in the first trimester fetal tissues exposed to maternal cigarette smoking.
abstract: Maternal cigarette smoking during pregnancy increases the risk of negative health consequences for the exposed child. Epigenetic mechanisms constitute a likely link between the prenatal exposure to maternal cigarette smoking and the increased risk in later life for diverse pathologies. Maternal smoking induces gene-specific DNA methylation alterations as well as global DNA hypermethylation in the term placentas and hypomethylation in the cord blood. Early pregnancy represents a developmental time where the fetal epigenome is remodeled and accordingly can be expected to be highly prone to exposures with an epigenetic impact. We have assessed the influence of maternal cigarette smoking during the first trimester for fetal global DNA methylation.
  
  
  
  We analyzed the human fetal intestines and livers as well as the placentas from the first trimester pregnancies. Global DNA methylation levels were quantified with ELISA using a methylcytosine antibody as well as with the bisulfite pyrosequencing of surrogate markers for global methylation status,LINE-1, andAluYb8. We identified gender-specific differences in global DNA methylation levels, but no significant DNA methylation changes in exposure responses to the first trimester maternal cigarette smoking.
  
  
  
  Acknowledging that only examining subsets of global DNA methylation markers and fetal sample availability represents possible limitations for the analyses, our presented results indicate that the first trimester maternal cigarette smoking is not manifested in immediate aberrations of fetal global DNA methylation.
authors.affiliation: Department of Biomedicine, Aarhus University, Bartholin building, DK-8000 Aarhus C, Denmark.|Faculty of Sciences, University of Novi Sad, Novi Sad, Serbia.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Fa
authors.affiliation: Department of Biomedicine, Aarhus University, Bartholin building, DK-8000 Aarhus C, Denmark.
authors.forename: Trine Vilsbøll
authors.initials: TV
authors.lastname: Larsen
authors.affiliation: Department of Biomedicine, Aarhus University, Bartholin building, DK-8000 Aarhus C, Denmark.
authors.forename: Katrine
authors.initials: K
authors.lastname: Bilde
authors.affiliation: Department of Biomedicine, Aarhus University, Bartholin building, DK-8000 Aarhus C, Denmark.
authors.forename: Tina F
authors.initials: TF
authors.lastname: Daugaard
authors.affiliation: Department of Biomedicine, Aarhus University, Bartholin building, DK-8000 Aarhus C, Denmark.
authors.forename: Emil H
authors.initials: EH
authors.lastname: Ernst
authors.affiliation: Department of Biomedicine, Aarhus University, Bartholin building, DK-8000 Aarhus C, Denmark.
authors.forename: Rasmus H
authors.initials: RH
authors.lastname: Olesen
authors.affiliation: Laboratory of Reproductive Biology, The Juliane Marie Centre for Women, Children and Reproduction, University Hospital of Copenhagen, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Linn S
authors.initials: LS
authors.lastname: Mamsen
authors.affiliation: Department of Biomedicine, Aarhus University, Bartholin building, DK-8000 Aarhus C, Denmark.|Department of Obstetrics and Gynecology, University Hospital of Aarhus, Skejby Sygehus, Aarhus, Denmark.
authors.forename: Erik
authors.initials: E
authors.lastname: Ernst
authors.affiliation: Department of Biomedicine, Aarhus University, Bartholin building, DK-8000 Aarhus C, Denmark.
authors.forename: Agnete
authors.initials: A
authors.lastname: Larsen
authors.affiliation: Department of Biomedicine, Aarhus University, Bartholin building, DK-8000 Aarhus C, Denmark.
authors.forename: Anders L
authors.identifier: 0000-0003-4372-9961
authors.initials: AL
authors.lastname: Nielsen
mesh_terms: D019175:DNA Methylation / Q000187:drug effects*; D044127:Epigenesis, Genetic / Q000187:drug effects; D005260:Female; D005312:Fetal Blood / Q000737:chemistry*; D006801:Humans; D018811:Maternal Exposure; D010920:Placenta / Q000737:chemistry*; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D012907:Smoking / Q000009:adverse effects*
keywords: DNA methylation; Epigenetics; Smoking; Toxicology; Xenochemicals