Presence of fetal DNA in maternal plasma and serum.
Author(s): Lo YM, Corbetta N, Chamberlain PF, Rai V, Sargent IL, Redman CW, Wainscoat JS
Publication: Lancet, 1997, Vol. 350, Page 485-7
PubMed ID: 9274585 PubMed Review Paper? No
Purpose of Paper
Conclusion of Paper
The purpose of this study was to determine the influence of blood component (plasma, serum, or nucleated blood cells) on the ability to detect circulating fetal DNA in maternal blood specimens. Specimens were collected into EDTA and plain tubes which were processed to obtain plasma and serum, respectively, within 3 h of collection. Separated plasma and serum were centrifuged a second time, transferred to a 3rd set of tubes, and frozen at -20 degrees C until analysis. DNA was extracted from the plasma and serum specimens by a rapid-boiling method. The red-cell pellet and buffy coat were saved from the initial plasma tube, and DNA was extracted from this portion by a Nucleon DNA extraction kit. Specimens from non-pregnant women and those carrying female fetuses were used as negative controls in a PCR to detect a fetus-derived Y sequence that was 198 bp long.
Summary of Findings:
The fetus-derived Y sequence was detected in 24 of the 30 EDTA plasma specimens and 21 of the 30 serum specimens from women carrying a male fetus. The PCR was only successful at detecting the Y signal for 5 of 30 nucleated blood-cell specimens from women carrying a male fetus. Seven of the 30 patients with male fetuses had discordant results between plasma and serum, and in 4 cases, the PCR results were negative with both the serum and plasma. The authors postulate that the concentration of fetal DNA in maternal blood may increase as gestation progresses, since 3 of these 4 cases were women tested at 15 weeks or earlier in their pregnancy, however, no statistical evaluation was presented.
Analyte Technology Platform DNA PCR
Classification Pre-analytical Factor Value(s) Preaquisition Diagnosis/ patient condition Pregnant
Biospecimen Aliquots and Components Blood and blood products Nucleated blood cells