Plasma gamma-globin gene expression suggests that fetal hematopoietic cells contribute to the pool of circulating cell-free fetal nucleic acids during pregnancy.

Abstract

BACKGROUND:

Reports of placental mRNA sequences in the plasma of pregnant women suggest that the placenta is the predominant source of cell-free fetal nucleic acids in maternal plasma during pregnancy. We developed an assay for gamma-globin mRNA concentrations to determine whether hematopoietic cells also contribute to the pool of fetal mRNA in maternal plasma.

METHODS:

Frozen paired plasma samples obtained from 40 women before and within 20 min after elective first-trimester termination of pregnancy (TOP) were analyzed. Fresh plasma samples from eight nonpregnant individuals were included as controls. Plasma gamma-globin mRNA was measured by use of real-time reverse transcription-PCR and analyzed with gestational age. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA was used to confirm the presence of cell-free RNA in each sample.

RESULTS:

gamma-Globin and GAPDH mRNA sequences were detected in every plasma sample. The concentrations of both messages were significantly increased in pregnancy (P <0.01). The concentrations of gamma-globin mRNA were decreased in most women after TOP, but gamma-globin mRNA was increased in some patients when TOP was performed later than 9 weeks of gestation.

CONCLUSIONS:

gamma-Globin mRNA sequences can be detected and measured in fresh and frozen plasma samples. Plasma gamma-globin and GAPDH mRNA concentrations are affected by pregnancy. The increased posttermination gamma-globin mRNA concentrations seen in some patients suggest that the source of this message is fetal hematopoietic cells. Further study in pregnant women after 9 weeks of gestation is necessary to evaluate the potential of gamma-globin mRNA as a marker for fetomaternal hemorrhage.

• Authors: Tuangsit Wataganara, Erik S LeShane, Angela Y Chen, Lynn Borgatta, Inga Peter, Kirby L Johnson, Diana W Bianchi
• Journal: Clinical chemistry (Clin Chem) Vol. 50 Issue 4 Pg. 689-93 (Apr 2004) ISSN: 0009-9147 [Print] England
• PMID: 15044329 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Nucleic Acids
• RNA, Messenger
• Globins

Topics

• Female
• Fetal Blood (cytology)
• Globins (biosynthesis, genetics)
• Hematopoietic Stem Cells (metabolism)
• Humans
• Male
• Mothers
• Nucleic Acids (blood)
• Pregnancy (blood)
• Pregnancy Trimesters
• RNA, Messenger (biosynthesis, blood)
• Reverse Transcriptase Polymerase Chain Reaction