The concentration of circulating corticotropin-releasing hormone mRNA in maternal plasma is increased in preeclampsia.
BACKGROUND
Increased fetal DNA in maternal plasma/serum has been reported in pregnancies complicated by preeclampsia. We hypothesize that fetal RNA may also be increased in maternal plasma in preeclampsia.


METHODS
We developed a real-time quantitative reverse transcription-PCR assay to measure the concentration of the mRNA of the corticotropin-releasing hormone (CRH) locus. Peripheral blood samples were obtained from healthy pregnant women both before and 2 h after delivery. Peripheral blood samples were also obtained from women suffering from preeclampsia and controls matched for gestational age. Plasma was harvested from these samples, and RNA was extracted. Plasma RNA was subjected to analysis by the reverse transcription-PCR assay.


RESULTS
CRH mRNA was detected in the plasma of 10 healthy pregnant women in the third trimester. CRH mRNA was found to be cleared very rapidly after cesarean section, with no detectable signal by 2 h postpartum. Plasma CRH mRNA concentrations were 1070 and 102 copies/mL, respectively, in 12 preeclamptic women and 10 healthy pregnant women matched for gestational age (Mann-Whitney test, P <0.001).


CONCLUSIONS
Plasma CRH mRNA represents a new molecular marker for preeclampsia. Maternal plasma RNA is gender- and polymorphism-independent and may allow noninvasive gene-expression profiling of an unborn fetus.
Ng
Enders K O
EK
Department of Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR.
Leung
Tse N
TN
Tsui
Nancy B Y
NB
Lau
Tze K
TK
Panesar
Nirmal S
NS
Chiu
Rossa W K
RW
Lo
Y M Dennis
YM
D001775:Blood Circulation; D003346:Corticotropin-Releasing Hormone / Q000097:blood* / Q000235:genetics; D005260:Female; D006801:Humans; D009035:Mothers; D049590:Postpartum Period; D011225:Pre-Eclampsia / Q000097:blood*; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D012333:RNA, Messenger / Q000097:blood*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D012333:RNA, Messenger; D003346:Corticotropin-Releasing Hormone