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Detection of Cell-Free DNA in Blood Plasma Samples of Cancer Patients
Published on: September 9, 2020
Early detection of cell-free fetal DNA in maternal plasma
S Illanes1, M Denbow, C Kailasam
1Fetal Medicine Research Unit, Division of Obstetrics and Gynaecology, University of Bristol, Bristol, UK. s.illanes@bristol.ac.uk
Objectives:
We aimed to establish the earliest gestational age at which fetal DNA in maternal plasma could be detected and whether this was reliable at 12-13 weeks' gestation.
Study Design:
A prospective observational cohort study of 32 pregnancies either after IVF or before prenatal diagnosis by CVS. Maternal blood was taken and RT-PCR was carried out to detect the multi-copy Y chromosome associated DSY14 gene. The end point was gender as assessed at delivery or on karyotype.
Results:
Y signal was obtained as early as 14 days post conception (4 weeks' gestation) and has a good prediction rate by 12 weeks' gestation.
Conclusion:
Free fetal DNA allows very early prediction of fetal sex in some cases and could be useful for clinical use for X-linked conditions by the end of the first trimester.
