@article{HaertleElHajjDittrichetal.2017,
  author    = {Haertle, Larissa and El Hajj, Nady and Dittrich, Marcus and M{\"u}ller, Tobias and Nanda, Indrajit and Lehnen, Harald and Haaf, Thomas},
  title     = {Epigenetic signatures of gestational diabetes mellitus on cord blood methylation},
  series = {Clinical Epigenetics},
  volume    = {9},
  journal   = {Clinical Epigenetics},
  number    = {28},
  doi       = {10.1186/s13148-017-0329-3},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-159459},
  year      = {2017},
  abstract  = {Background: Intrauterine exposure to gestational diabetes mellitus (GDM) confers a lifelong increased risk for metabolic and other complex disorders to the offspring. GDM-induced epigenetic modifications modulating gene regulation and persisting into later life are generally assumed to mediate these elevated disease susceptibilities. To identify candidate genes for fetal programming, we compared genome-wide methylation patterns of fetal cord bloods (FCBs) from GDM and control pregnancies. Methods and results: Using Illumina's 450K methylation arrays and following correction for multiple testing, 65 CpG sites (52 associated with genes) displayed significant methylation differences between GDM and control samples. Four candidate genes, ATP5A1, MFAP4, PRKCH, and SLC17A4, from our methylation screen and one, HIF3A, from the literature were validated by bisulfite pyrosequencing. The effects remained significant after adjustment for the confounding factors maternal BMI, gestational week, and fetal sex in a multivariate regression model. In general, GDM effects on FCB methylation were more pronounced in women with insulin-dependent GDM who had a more severe metabolic phenotype than women with dietetically treated GDM. Conclusions: Our study supports an association between maternal GDM and the epigenetic status of the exposed offspring. Consistent with a multifactorial disease model, the observed FCB methylation changes are of small effect size but affect multiple genes/loci. The identified genes are primary candidates for transmitting GDM effects to the next generation. They also may provide useful biomarkers for the diagnosis, prognosis, and treatment of adverse prenatal exposures.},
  language  = {en}
}
@article{MaierhoferFlunkertDittrichetal.2017,
  author    = {Maierhofer, Anna and Flunkert, Julia and Dittrich, Marcus and M{\"u}ller, Tobias and Schindler, Detlev and Nanda, Indrajit and Haaf, Thomas},
  title     = {Analysis of global DNA methylation changes in primary human fibroblasts in the early phase following X-ray irradiation},
  series = {PLoS ONE},
  volume    = {12},
  journal   = {PLoS ONE},
  number    = {5},
  doi       = {10.1371/journal.pone.0177442},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170895},
  pages     = {e0177442},
  year      = {2017},
  abstract  = {Epigenetic alterations may contribute to the generation of cancer cells in a multi-step process of tumorigenesis following irradiation of normal body cells. Primary human fibroblasts with intact cell cycle checkpoints were used as a model to test whether X-ray irradiation with 2 and 4 Gray induces direct epigenetic effects (within the first cell cycle) in the exposed cells. ELISA-based fluorometric assays were consistent with slightly reduced global DNA methylation and hydroxymethylation, however the observed between-group differences were usually not significant. Similarly, bisulfite pyrosequencing of interspersed LINE-1 repeats and centromeric α-satellite DNA did not detect significant methylation differences between irradiated and non-irradiated cultures. Methylation of interspersed ALU repeats appeared to be slightly increased (one percentage point; p = 0.01) at 6 h after irradiation with 4 Gy. Single-cell analysis showed comparable variations in repeat methylation among individual cells in both irradiated and control cultures. Radiation-induced changes in global repeat methylation, if any, were much smaller than methylation variation between different fibroblast strains. Interestingly, α-satellite DNA methylation positively correlated with gestational age. Finally, 450K methylation arrays mainly targeting genes and CpG islands were used for global DNA methylation analysis. There were no detectable methylation differences in genic (promoter, 5' UTR, first exon, gene body, 3' UTR) and intergenic regions between irradiated and control fibroblast cultures. Although we cannot exclude minor effects, i.e. on individual CpG sites, collectively our data suggest that global DNA methylation remains rather stable in irradiated normal body cells in the early phase of DNA damage response.},
  language  = {en}
}