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CC BY-NC-ND 4.0 · AJP Rep 2018; 08(01): e18-e24
DOI: 10.1055/s-0038-1627473
Case Report
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Differential Methylation of Syncytin-1 and 2 Distinguishes Fetal Growth Restriction from Physiologic Small for Gestational Age

Sami P. Makaroun
1   Division of Maternal Fetal Medicine, Magee-Womens Research Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
2   Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania
,
Katherine P. Himes
1   Division of Maternal Fetal Medicine, Magee-Womens Research Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
2   Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania
› Author Affiliations Funding Source This work was supported by the Reproductive Scientist Development Program grant NIH K12 HD000849 (K.P.H.) and National Institutes of Health Grants K12 HD063087 (K.P.H.)
Further Information

Publication History

26 August 2016

09 December 2017

Publication Date:
21 February 2018 (online)

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Abstract

Objective The retroviral genes encoding Syncytin-1 (SYN1) and Syncytin-2 (SYN2) are epigenetically regulated, uniquely expressed in the placenta and critical to placental function. We sought to determine if placental expression and methylation patterns of SYN1 and SYN2 from pregnancies complicated by fetal growth restriction (FGR) differed from physiologic small for gestational age (SGA) and appropriate for gestational age (AGA) controls.

Study Design Placental biopsies were obtained from AGA, SGA and FGR neonates delivered at >36 weeks gestation. SGA and FGR were defined as birth weight <10% with FGR additionally requiring abnormal fetal testing. We quantified DNA methylation of SYN1 and SYN2 by EpiTyper and gene expression by RT-qPCR.

Results We identified 10 AGA, 9 SGA and 7 FGR placentas. There was decreased methylation in SYN1 and SYN2 in FGR relative to AGA and SGA. When the sum of SYN1 and SYN2 methylation was used for prediction of FGR from SGA, the area under the receiver operator characteristic curve was 0.9048 (0.7602, 1).

Conclusion SYN1 and SYN2 methylation marks differ in FGR and SGA. We plan future studies to examine these markers in cell free DNA to determine if these methylation changes could be used as a biomarker for FGR.

Keywords

retroelements - syncytin - methylation - placenta - fetal growth restriction - intrauterine growth restriction

Presentation Information

Findings presented at the 36th Annual Pregnancy Meeting, Society for Maternal Fetal Medicine, Atlanta, Georgia, February 1–6, 2016


 

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