Unknown,Transcriptomics,Genomics,Proteomics

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Overlapping DNA methylation profile between placentas with trisomy 16 and early-onset preeclampsia

ABSTRACT: Preeclampsia is one of the leading causes of maternal death worldwide. While the root cause is still unknown, the underlying biology of the disorder is becoming more clear. We recently published a study showing large, significant differences in DNA methylation in 3rd trimester placental samples associated with early-onset preeclampsia (EOPET) compared to controls. In this study, to identify DNA methylation differences associated with preeclampsia that occur early in pregnancy and to further delineate common EOPET-associated differences, we utilized a genetic defect, trisomy 16 (T16), that is predisposing to preeclampsia. We ran T16 placental samples from the 1st trimester (n=5) and 3rd trimester (n=10) against gestational age matched controls on the Illumina Infinium HumanMethylation450 BeadChip. Third trimester samples were from pregnancies with T16 confined to the placenta (confined placental mosaicism 16;CPM16), and consisted of samples that were and were not associated with EOPET (n=5 each). We identified a large number of DNA methylation differences in CPM16 samples compared to controls using stringent criteria (n=2254;False Discovery Rate <0.01, ->0.15). Several of these differences (11%) overlapped differences observed in chromosomally normal EOPET using similarly stringent criteria (FDR<0.01;->0.125). Isolating EOPET-associated probes produced a similar - distribution amongst CPM16 samples, although samples associated with EOPET showed a tendency towards larger DNA methylation differences. We also identified 262 DNA methylation differences between 1st trimester T16 and 1st trimester controls. Of these, 77 overlapped differences seen in 3rd trimester CPM16. Investigating these 77 T16/CPM16 specific DNA methylation differences, we identified three probes near two genes (ARGHEF37 and JUNB) that were also present as EOPET-associated methylation differences. In summary, we identified significant overlapping DNA methylation profiles of placentas with T16 and chromosomally normal placentas associated with EOPET. Specific DNA methylation marks within these profiles may be of future clinical utility in early identification of pregnancies susceptible to EOPET. Bisulfite converted DNA from 5 1st trimester trisomy 16 placentas, 5 chromosomally normal 1st trimester placentas, 10 third trimester placentas from confined placental mosaicism placentas and 10 chromosomally normal 3rd trimester placentas

ORGANISM(S): Homo sapiens

SUBMITTER: John Blair

PROVIDER: E-GEOD-49343 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Overlapping DNA methylation profile between placentas with trisomy 16 and early-onset preeclampsia

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