Reproductive Sciences

, Volume 18, Issue 11, pp 1085–1091 | Cite as

Reduced Expression of Both Syncytin 1 and Syncytin 2 Correlates With Severity of Preeclampsia

  • Amandine Vargas
  • Chirine Toufaily
  • Frédérique LeBellego
  • Éric Rassart
  • Julie Lafond
  • Benoit BarbeauEmail author
Original Articles


Human endogenous retroviruses (HERVs) represent up to 8% of the human genome and express several of its genes in the placenta. Studies have demonstrated that HERV envelope proteins syncytins 1 and 2 play a crucial role in trophoblast fusion and placenta development. Here, we compared the levels of placental expression of syncytins with the severity of preeclampsia (PE) symptoms. Confocal microscopy experiments indicated a pronounced deficiency in cellular fusion in trophoblast cells from patients with PE when compared to controls. As determined by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and Western blot analyses, syncytin mRNA and protein levels were decreased in PE placentas versus controls. Interestingly, syncytin 2 levels were more importantly impaired than syncytin 1. Our results further highlighted the existence of a correlation between the extent of the decrease in the expression levels of both fusogenic proteins and the degree of severity of PE symptoms. These HERV proteins could thereby be used as potential markers for the early diagnosis of PE.


HERV syncytin cytotrophoblasts fusion preeclampsia 


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Copyright information

© Society for Reproductive Investigation 2011

Authors and Affiliations

  • Amandine Vargas
    • 1
  • Chirine Toufaily
    • 1
  • Frédérique LeBellego
    • 1
  • Éric Rassart
    • 1
  • Julie Lafond
    • 1
  • Benoit Barbeau
    • 1
    Email author
  1. 1.Département des sciences biologiques and Centre de recherche BioMedUniversité du Québec à MontréalMontréalCanada

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