title: Discovery of epigenetic biomarkers for the noninvasive diagnosis of fetal disease.
abstract: OBJECTIVE
  The primary goal of this study was to identify CpG sites in the human genome that are differentially methylated in DNA obtained from chorionic villus sampling (CVS) samples and gestational age-matched maternal blood cell (MBC) samples.
  
  
  METHODS
  We used the HumanMethylation27 DNA Analysis BeadChip to characterize DNA methylation in samples of CVS and MBC. We then selected a subset of differentially methylated CpG sites on chromsome 13 and subjected them to analysis by mass spectrometry using the Epityper platform.
  
  
  RESULTS
  We identified 718 tissue-specific differentially methylated regions (DMRs) between MBC and CVS; 563 of these were hypermethylated in MBC and hypomethylated in CVS, whereas 155 sites were hypomethylated in MBC and hypermethylated in CVS. Further analysis of 13 DMRs on chromosome 13 by Epityper confirmed the microarray data and provided us with additional data about the methylation patterns of surrounding CpG sites.
  
  
  CONCLUSIONS
  Analysis of the resulting data identified a large number of cytosine-guanine dinucleotides that are potential biomarkers for the selective amplification of fetal DNA from maternal plasma and the subsequent noninvasive detection of trisomy 13.
authors.affiliation: Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, PA, USA.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Bunce
authors.forename: Tianjiao
authors.initials: T
authors.lastname: Chu
authors.forename: Urvashi
authors.initials: U
authors.lastname: Surti
authors.forename: William Allen
authors.initials: WA
authors.lastname: Hogge
authors.forename: David G
authors.initials: DG
authors.lastname: Peters
mesh_terms: D015193:Chorionic Villi Sampling; D002882:Chromosomes, Human, Pair 13 / Q000235:genetics; D004247:DNA / Q000097:blood; D019175:DNA Methylation; D015226:Dinucleoside Phosphates / Q000235:genetics; D044127:Epigenesis, Genetic / Q000235:genetics*; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis* / Q000235:genetics*; D005819:Genetic Markers; D005865:Gestational Age; D006801:Humans; D046228:Microarray Analysis; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*
chemical_list: D004247:DNA; D015226:Dinucleoside Phosphates; D005819:Genetic Markers; C015772:CpG dinucleotide