Dataset Information

Epigenetic signature of birth-weight discordance in Danish twins

ABSTRACT: Epigenetic profiling of birth-weight discordant twins using Illumina's 450K Human DNA methylation BeadChip Comparing DNA methylation difference in birth-weight discordant twin pairs

ORGANISM(S): Homo sapiens

SUBMITTER: Lene Christiansen Qihua Tan Morten Frost

PROVIDER: E-GEOD-61496 | ArrayExpress | 2014-12-15

SECONDARY ACCESSION(S): GSE61496PRJNA261326

REPOSITORIES: GEO, ArrayExpress

ACCESS DATA

Publications

Epigenetic signature of birth weight discordance in adult twins.

Tan Qihua Q Frost Morten M Heijmans Bastiaan T BT von Bornemann Hjelmborg Jacob J Tobi Elmar W EW Christensen Kaare K Christiansen Lene L

BMC genomics 20141204

BACKGROUND: A low birth weight has been extensively related to poor adult health outcomes. Birth weight can be seen as a proxy for environmental conditions during prenatal development. Identical twin pairs discordant for birth weight provide an extraordinary model for investigating the association between birth weight and adult life health while controlling for not only genetics but also postnatal rearing environment. We performed an epigenome-wide profiling on blood samples from 150 pairs of ad ...[more]

PMID: 25476734

Similar Datasets

Project description:Age-related changes in DNA methylation occurring in blood leukocytes during early childhood may reflect epigenetic maturation. We hypothesized that some of these changes involve gene networks of critical relevance in leukocyte biology and conducted a prospective study to elucidate the dynamics of DNA methylation. Serial blood samples were collected at 3, 6, 12, 24, 36, 48 and 60 months after birth in 10 healthy girls born in Finland and participating in the Type 1 Diabetes Prediction and Prevention Study. DNA methylation was measured using the HumanMethylation450 BeadChip. After filtering for the presence of polymorphisms and cell-lineage-specific signatures, 794 CpGs showed significant DNA methylation differences as a function of age in all children (41.5% age-methylated and 58.4% age-demethylated, bonferroni corrected p-value <0.001). Age-methylated CpGs were more frequently located in gene bodies and within +5 to +50 kilobases (kb) of transcription start sites (TSS), and enriched in developmental, neuronal and plasma membrane genes. Age-demethylated CpGs were associated to promoters and DNAse-I hypersensitivity sites, located within -5 to +5 kb of the nearest TSS, and enriched in genes related to immunity, antigen presentation, the polycomb-group protein complex and cytoplasm. This study reveals that susceptibility loci for complex inflammatory diseases (e.g. IRF5, NOD2, PTGER4) and genes encoding histone modifiers and chromatin remodeling factors (e.g. HDAC4, KDM2A, KDM2B, JARID2, ARID3A, SMARCD3) undergo DNA methylation changes in leukocytes during early childhood. These results open new perspectives to understand leukocyte maturation and provide a catalog of CpGs that may need to be corrected for age effects when performing DNA methylation studies in children. We analysed the longitudinal changes in DNA methylation in a total of 60 samples at 3, 6, 12, 24, 36, 48, and 60 months after birth, using serial DNA samples extracted from peripheral blood leukocytes of 10 healthy girls of the Diabetes Prediction and Prevention Study (DIPP).

Project description:Background: Low birth weight is associated with an increased adult metabolic disease risk. It is widely discussed that poor intrauterine conditions could induce long-lasting epigenetic modifications, leading to systemic changes in regulation of metabolic genes. In a unique cohort of 17 monozygotic (MZ) monochorionic female twins very discordant for birth weight (relative differences ranging from 21.3-35.7%), we examined if adverse prenatal growth conditions experienced by the smaller co-twins lead to systemic long-lasting DNA methylation changes. Genome-wide DNA methylation profiles were acquired from saliva DNA using the Infinium HumanMethylation450 BeadChip, targeting ~2% of all CpGs in the genome. Results: Overall, co-twins showed very similar genome-wide DNA methylation profiles. Since observed differences were almost exclusively caused by variable cellular composition, an original marker-based adjustment strategy was developed to eliminate such variation at affected CpGs. Among adjusted and unchanged CpGs 3153 were differentially methylated between the heavy and light co-twins at nominal significance (p<0.01), of which 45 showed absolute mean β-value differences >0.05 (max=0.08). Deep bisulfite sequencing of eight such loci revealed that differences remained in the range of technical variation, arguing against a reproducible biological effect. Analysis of methylation in repetitive elements using methylation-dependent primer extension assays also indicated no significant intra-pair differences. Conclusions: Severe intrauterine growth differences observed within these MZ twins are not associated with long-lasting DNA methylation differences in cells composing saliva, detectable with up-to-date technologies. Additionally, our results indicate that uneven cell type composition can lead to spurious results and should be addressed in epigenomic studies. DNA methylation profiles of saliva from 17 Adult Female MZ MC Twins discordant for birth weight.