[Expression and methylated regulation of HERVWE1 in placenta of monozygotic discordant twins].

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).

CONCLUSION

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.