title: Early gestation as the critical time-window for changes in the prenatal environment to affect the adult human blood methylome.
abstract: BACKGROUND
  The manipulation of pregnancy diets in animals can lead to changes in DNA methylation with phenotypic consequences in the offspring. Human studies have concentrated on the effects of nutrition during early gestation. Lacking in humans is an epigenome-wide association study of DNA methylation in relation to perturbations in nutrition across all gestation periods.
  
  
  METHODS
  We used the quasi-experimental setting of the Dutch famine of 1944-45 to evaluate the impact of famine exposure during specific 10-week gestation periods, or during any time in gestation, on genome-wide DNA methylation levels at age ∼ 59 years. In addition, we evaluated the impact of exposure during a shorter pre- and post-conception period. DNA methylation was assessed using the Illumina 450k array in whole blood among 422 individuals with prenatal famine exposure and 463 time- or sibling-controls without prenatal famine exposure.
  
  
  RESULTS
  Famine exposure during gestation weeks 1-10, but not weeks 11-20, 21-30 or 31-delivery, was associated with an increase in DNA methylation of CpG dinucleotides cg20823026 (FAM150B), cg10354880 (SLC38A2) and cg27370573 (PPAP2C) and a decrease of cg11496778 (OSBPL5/MRGPRG) (P < 5.9 × 10(-7), PFDR < 0.031). There was an increase in methylation of TACC1 and ZNF385A after exposure during any time in gestation (P < 2.0 × 10(-7), PFDR = 0.034) and a decrease of cg23989336 (TMEM105) after exposure around conception. These changes represent a shift of 0.3-0.6 standard deviations and are linked to genes involved in growth, development and metabolism.
  
  
  CONCLUSIONS
  Early gestation, and not mid or late gestation, is identified as a critical time-period for adult DNA methylation changes in whole blood after prenatal exposure to famine.
authors.affiliation: Molecular Epidemiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Elmar W
authors.initials: EW
authors.lastname: Tobi
authors.affiliation: Molecular Epidemiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Roderick C
authors.initials: RC
authors.lastname: Slieker
authors.affiliation: Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia USA.
authors.forename: Aryeh D
authors.initials: AD
authors.lastname: Stein
authors.affiliation: Molecular Epidemiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: H Eka D
authors.initials: HE
authors.lastname: Suchiman
authors.affiliation: Molecular Epidemiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: P Eline
authors.initials: PE
authors.lastname: Slagboom
authors.affiliation: Medical Statistics and Bioinformatics, Leiden University Medical Center, Leiden, The Netherlands and.
authors.forename: Erik W
authors.initials: EW
authors.lastname: van Zwet
authors.affiliation: Molecular Epidemiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Bastiaan T
authors.initials: BT
authors.lastname: Heijmans
authors.affiliation: Molecular Epidemiology, Leiden University Medical Center, Leiden, The Netherlands, Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York USA lumey@columbia.edu.
authors.forename: L H
authors.initials: LH
authors.lastname: Lumey
mesh_terms: D016022:Case-Control Studies; D019175:DNA Methylation; D004777:Environment; D005260:Female; D049673:History, 20th Century; D006801:Humans; D008297:Male; D039382:Maternal Nutritional Physiological Phenomena; D008875:Middle Aged; D009426:Netherlands; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011297:Prenatal Exposure Delayed Effects / Q000235:genetics*; D013217:Starvation / Q000266:history*
keywords: DNA methylation, prenatal, Dutch Famine, Hunger Winter, exposure, nutrition