OBJECTIVE: To test the hypothesis that free fetal DNA (ffDNA) circulating in maternal plasma originates mainly from the placenta we studied ffDNA levels in anembryonic pregnancies. METHODS: Maternal blood samples were collected from 15 normal first-trimester pregnancies in which fetal sex was subsequently determined and nine patients with a diagnosis of anembryonic gestation (AG). The Y chromosome DYS14 gene was quantified by real-time quantitative PCR (RT-PCR) for the determination of fetal sex in both plasma and chorionic tissue samples. Fetal sex in chorionic tissue samples was also determined using quantitative fluorescence PCR (QF-PCR). RESULTS: The correct sex result was obtained from maternal plasma in all. Four AG pregnancies were female (DYS14 negative) results. In five of the AG cases, the chorionic tissue was found to be male (by both QF-PCR and RT-PCR which agreed) and positive male signal was found in maternal plasma by RT-PCR. There was no statistical difference between median free fetal DNA concentration in plasma between the AG male cases (148.3 GE/mL) and controls (145.8 GE/mL). CONCLUSION: Since ffDNA levels are normal in pregnancies without a fetus, the data support the hypothesis that the trophoblastic cells are the major source ffDNA in maternal plasma.
OBJECTIVE: To test the hypothesis that free fetal DNA (ffDNA) circulating in maternal plasma originates mainly from the placenta we studied ffDNA levels in anembryonic pregnancies. METHODS: Maternal blood samples were collected from 15 normal first-trimester pregnancies in which fetal sex was subsequently determined and nine patients with a diagnosis of anembryonic gestation (AG). The Y chromosome DYS14 gene was quantified by real-time quantitative PCR (RT-PCR) for the determination of fetal sex in both plasma and chorionic tissue samples. Fetal sex in chorionic tissue samples was also determined using quantitative fluorescence PCR (QF-PCR). RESULTS: The correct sex result was obtained from maternal plasma in all. Four AG pregnancies were female (DYS14 negative) results. In five of the AG cases, the chorionic tissue was found to be male (by both QF-PCR and RT-PCR which agreed) and positive male signal was found in maternal plasma by RT-PCR. There was no statistical difference between median free fetal DNA concentration in plasma between the AG male cases (148.3 GE/mL) and controls (145.8 GE/mL). CONCLUSION: Since ffDNA levels are normal in pregnancies without a fetus, the data support the hypothesis that the trophoblastic cells are the major source ffDNA in maternal plasma.
Authors: Ming Zhang; Tao Li; Jingyi Chen; Li Li; Chun Zhou; Yan Wang; Wenhui Liu; Yuanzhen Zhang Journal: J Huazhong Univ Sci Technolog Med Sci Date: 2011-10-25
Authors: Ji Hyae Lim; Bom Yi Lee; Jin Woo Kim; You Jung Han; Jin Hoon Chung; Min Hyoung Kim; Dong Wook Kwak; So Yeon Park; Hee Back Choi; Hyun Mee Ryu Journal: J Assist Reprod Genet Date: 2018-02-08 Impact factor: 3.412
Authors: Jason C H Tsang; Joaquim S L Vong; Lu Ji; Liona C Y Poon; Peiyong Jiang; Kathy O Lui; Yun-Bi Ni; Ka Fai To; Yvonne K Y Cheng; Rossa W K Chiu; Yuk Ming Dennis Lo Journal: Proc Natl Acad Sci U S A Date: 2017-08-22 Impact factor: 11.205