title: [Expression and methylated regulation of HERVWE1 in placenta of monozygotic discordant twins].
abstract: OBJECTIVE
  To explore the HERVWE1 gene expression in the placentas of discordant monozygotic twins and identify its regulation by methylation.
  
  
  METHODS
  Fetuses from 21 pairs of monozygotic discordant twins were marked as "smaller" or "larger" according to birth weight. Placental HERVWE1 mRNA and protein expression profiles were analyzed by quantitative reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC) stain. Methylation profiles of the HERVWE1 promoter region were analyzed by COBRA, MSP-PCR and pyrosequencing assay.
  
  
  RESULTS
  In discordant twins group, the mean methylation level of the HERVWE1 promoter region decreased in smaller fetuses (P < 0.05). And there were increased mRNA and protein levels of HERVWE1 in smaller fetuses versus larger counterparts (P < 0.05).
  
  
  CONCLUSIONS
  In discordant monozygotic twins, the HERVWE1 expression is higher in smaller fetuses and lower in larger counterparts. Methylation of HERVWE1 gene promoter region may participate in the regulation of HERVWE1 gene expression in twins.
authors.affiliation: Fetal Medicine Center, Department of Obstetrics and Gynecology, First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Gao
authors.forename: Zhi-ming
authors.initials: ZM
authors.lastname: He
authors.forename: Jin-ping
authors.initials: JP
authors.lastname: Li
authors.forename: Yan-min
authors.initials: YM
authors.lastname: Luo
authors.forename: Hong-yu
authors.initials: HY
authors.lastname: Sun
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.forename: Lin-huan
authors.initials: LH
authors.lastname: Huang
authors.forename: Xuan
authors.initials: X
authors.lastname: Huang
authors.forename: Man-chao
authors.initials: MC
authors.lastname: Li
authors.forename: Shi-wen
authors.initials: SW
authors.lastname: Jiang
authors.forename: Qun
authors.initials: Q
authors.lastname: Fang
mesh_terms: D019175:DNA Methylation; D020077:Endogenous Retroviruses / Q000235:genetics*; D005260:Female; D005317:Fetal Growth Retardation / Q000235:genetics*; D015870:Gene Expression; D015686:Gene Products, env / Q000235:genetics* / Q000378:metabolism; D005814:Genes, Viral / Q000235:genetics; D006801:Humans; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000235:genetics* / Q000378:metabolism; D014430:Twins, Monozygotic / Q000235:genetics*
chemical_list: D015686:Gene Products, env; D011257:Pregnancy Proteins; C405335:syncytin