title: Association between birth weight and DNA methylation of IGF2, glucocorticoid receptor and repetitive elements LINE-1 and Alu.
abstract: OBJECTIVE
  We examined the association between birth weight and methylation in the imprinted IGF/H19 loci, the nonimprinted gene NR3C1 and repetitive element DNA (LINE-1 and Alu).
  
  
  METHODS
  We collected umbilical cord venous blood from 219 infants born in Mexico City (Mexico) as part of a prospective birth cohort study and analyzed DNA methylation using pyrosequencing.
  
  
  RESULTS
  Birth weight was not associated with DNA methylation of the regions studied. One of the CpG dinucleotides in the IGF2 imprinting control region (ICR)1 includes a potential C-T SNP. Among individuals with an absence of methylation at this site, probably due to a paternally inherited T allele, birth weight was associated with mean methylation status of both IGF2 ICR1 and ICR2. However, this association would not have survived adjustment for multiple testing.
  
  
  CONCLUSIONS
  While we did not detect an association between DNA methylation and birth weight, our study suggests a potential gene-epigene interaction between a T allele in the IGF2 ICR1 and methylation of ICRs of IGF2, and fetal growth.
authors.affiliation: Department of Neonatology, Beth Israel Deaconess Medical Center & Division of Newborn Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA. heburris@bidmc.harvard.edu
authors.forename: Heather H
authors.initials: HH
authors.lastname: Burris
authors.forename: Joe M
authors.initials: JM
authors.lastname: Braun
authors.forename: Hyang-Min
authors.initials: HM
authors.lastname: Byun
authors.forename: Letizia
authors.initials: L
authors.lastname: Tarantini
authors.forename: Adriana
authors.initials: A
authors.lastname: Mercado
authors.forename: Rosalind J
authors.initials: RJ
authors.lastname: Wright
authors.forename: Lourdes
authors.initials: L
authors.lastname: Schnaas
authors.forename: Andrea A
authors.initials: AA
authors.lastname: Baccarelli
authors.forename: Robert O
authors.initials: RO
authors.lastname: Wright
authors.forename: Martha M
authors.initials: MM
authors.lastname: Tellez-Rojo
mesh_terms: D000328:Adult; D020087:Alu Elements / Q000235:genetics*; D001724:Birth Weight / Q000235:genetics*; D015331:Cohort Studies; D018899:CpG Islands; D019175:DNA Methylation; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007335:Insulin-Like Growth Factor II / Q000235:genetics* / Q000378:metabolism; D020084:Long Interspersed Nucleotide Elements / Q000235:genetics*; D008297:Male; D020641:Polymorphism, Single Nucleotide; D011446:Prospective Studies; D011965:Receptors, Glucocorticoid / Q000235:genetics*; D017422:Sequence Analysis, DNA
chemical_list: D011965:Receptors, Glucocorticoid; D007335:Insulin-Like Growth Factor II