title: Maternal plasma RNA sequencing for genome-wide transcriptomic profiling and identification of pregnancy-associated transcripts.
abstract: BACKGROUND
  Analysis of circulating RNA in the plasma of pregnant women has the potential to serve as a powerful tool for noninvasive prenatal testing and research. However, detection of circulating RNA in the plasma in an unbiased and high-throughput manner has been technically challenging. Therefore, only a limited number of circulating RNA species in maternal plasma have been validated as pregnancy- and placenta-specific biomarkers.
  
  
  METHODS
  We explored the use of massively parallel sequencing for plasma transcriptome profiling in first-, second-, and third-trimester pregnant women. Genotyping was performed for amniotic fluid, placental tissues, and maternal blood cells, with exome-enriched sequencing.
  
  
  RESULTS
  In the early pregnancy group comprising 1 first- and 1 second-trimester pregnancy cases, the fetal contribution to the RNA pool in maternal plasma was 3.70%. The relative proportion of fetal contribution was increased to 11.28% in the late pregnancy group comprising 2 third-trimester pregnancy cases. The placental biallelic expression pattern of PAPPA (pregnancy-associated plasma protein A, pappalysin 1), a known pregnancy-specific gene, and the monoallelic expression pattern of H19 [H19, imprinted maternally expressed transcript (non-protein coding)], an imprinted maternally expressed gene, were also detected in the maternal plasma. Furthermore, by direct examination of the maternal plasma transcriptomic profiles before and after delivery, we identified a panel of pregnancy-associated genes.
  
  
  CONCLUSIONS
  Plasma RNA sequencing provides a holistic view of the maternal plasma transcriptomic repertoire. This technology is potentially valuable for using circulating plasma nucleic acids for prenatal testing and research.
authors.affiliation: Centre for Research into Circulating Fetal Nucleic Acids, Li Ka Shing Institute of Health Sciences, Department of Chemical Pathology, and.
authors.forename: Nancy B Y
authors.initials: NB
authors.lastname: Tsui
authors.affiliation: Centre for Research into Circulating Fetal Nucleic Acids, Li Ka Shing Institute of Health Sciences, Department of Chemical Pathology, and.
authors.forename: Peiyong
authors.initials: P
authors.lastname: Jiang
authors.affiliation: Centre for Research into Circulating Fetal Nucleic Acids, Li Ka Shing Institute of Health Sciences, Department of Chemical Pathology, and.
authors.forename: Yuen Fei
authors.initials: YF
authors.lastname: Wong
authors.affiliation: Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Hong Kong SAR, China.
authors.forename: Tak Y
authors.initials: TY
authors.lastname: Leung
authors.affiliation: Centre for Research into Circulating Fetal Nucleic Acids, Li Ka Shing Institute of Health Sciences, Department of Chemical Pathology, and.
authors.forename: K C Allen
authors.initials: KC
authors.lastname: Chan
authors.affiliation: Centre for Research into Circulating Fetal Nucleic Acids, Li Ka Shing Institute of Health Sciences, Department of Chemical Pathology, and.
authors.forename: Rossa W K
authors.initials: RW
authors.lastname: Chiu
authors.affiliation: Centre for Research into Circulating Fetal Nucleic Acids, Li Ka Shing Institute of Health Sciences, Department of Chemical Pathology, and.
authors.forename: Hao
authors.initials: H
authors.lastname: Sun
authors.affiliation: Centre for Research into Circulating Fetal Nucleic Acids, Li Ka Shing Institute of Health Sciences, Department of Chemical Pathology, and loym@cuhk.edu.hk.
authors.forename: Y M Dennis
authors.initials: YM
authors.lastname: Lo
mesh_terms: D000653:Amniotic Fluid / Q000378:metabolism; D059472:Exome; D005260:Female; D005333:Fetus; D020869:Gene Expression Profiling; D015894:Genome, Human; D006801:Humans; D010920:Placenta / Q000378:metabolism; D020641:Polymorphism, Single Nucleotide; D011247:Pregnancy / Q000097:blood / Q000235:genetics*; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D011263:Pregnancy Trimester, Third; D012313:RNA / Q000097:blood / Q000235:genetics*; D017423:Sequence Analysis, RNA
chemical_list: D012313:RNA