Circulating cell‐free fetal DNA for the detection of RHD status and sex using reflex fetal identifiers1. (6th December 2012)

• Record Type: Journal Article
• Authors: Moise, K. J.; Boring, N. H.; O'Shaughnessy, R.; Simpson, L. L.; Wolfe, H. M.; Baxter, J. K.; Polzin, W.; Eddleman, K. A.; Hassan, S. S.; Skupski, D.; McLennan, G.; Paladino, T.; Oeth, P.; Bombard, A.
• Is Part Of: Prenatal diagnosis. Volume 33:Number 1(2013:Jan.)
• Page Start: 95
• Page End: 101
• Publication Date: 2012-12-06
• Subjects: Prenatal diagnosis -- Periodicals; Fetus -- Diseases -- Diagnosis -- Periodicals; Electronic journals; 618.32075
• DOI: 10.1002/pd.4018
• Languages: English
• ISSNs: 0197-3851

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <sec id="pd4018-sec-0001" sec-type="section"> <title>Objective</title> <p>To determine the sensitivity and specificity of circulating cell‐free fetal DNA in determining the fetal RHD status and fetal sex.</p> </sec> <sec id="pd4018-sec-0002" sec-type="section"> <title>Methods</title> <p>Maternal blood was collected in each trimester of pregnancy from RhD negative nonalloimmunized women. Whole blood was centrifuged, separated into plasma and buffy coat, and frozen at –80°C. DNA analysis was conducted via allele‐specific primer extensions for exons 4, 5, and 7 of the <italic>RHD</italic> gene and for a 37‐base pair insertion in exon 4 (<italic>RHD</italic> pseudogene; psi) three Y‐chromosome sequences (SRY, DBY, and TTY2), and an extraction control (TGIFL‐like X/Y). RhD serotyping on cord blood and gender assessment of the newborns were entered into a Web‐based database.</p> </sec> <sec id="pd4018-sec-0003" sec-type="section"> <title>Results</title> <p>One hundred twenty women were enrolled. The median gestational age at the first venipuncture was 12.4 (range: 10.6–13.9) weeks with 120 samples drawn; 118 samples were drawn at 17.6 (16–20.9) weeks; and 113 samples at 28.7 (27.9–33.9) weeks. Overall accuracy for RHD was 99.1%, 99.1%, and 98.1% for each trimester and was 99.1%, 99.1%, and 100% for fetal sex determination.</p> </sec> <sec id="pd4018-sec-0004" sec-type="section"> <title>Conclusions</title> <p>Fetal RHD genotyping and sex can be very accurately determined in all three trimesters using circulating cell‐free fetal DNA in the maternal circulation. © 2012 John Wiley & Sons, Ltd.</p> </sec> </abstract>