Maternal urinary cell free fetal DNA in relation to gestational age

• Published in: Middle East Fertility Society journal Vol. 21; no. 4; pp. 241 - 245
• Main Authors: Shaban, Mona Mohamed, Salah Eldin, Noha Mohamed, Kandil, Hisham Omar, Aly Hassan, Zeinab, Rabie, Walaa A., Elgarf, Wael, Talaat Elrayes, Mohamed
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2016; SpringerOpen
• Subjects: Cell free fetal DNA; Gestational age; Maternal urine; Prenatal diagnosis; Cell free fetal DNA; Prenatal diagnosis; Maternal urine; Gestational age
• ISSN: 1110-5690
• DOI: 10.1016/j.mefs.2016.04.001

Objectives: To evaluate the presence of cell-free fetal DNA in the maternal urine in relation to gestational age as a potential source for non-invasive prenatal diagnosis. Material and methods: One hundred and sixty normal pregnant women were included in the study; 80 women pregnant with male fetuses and 80 women pregnant with female fetuses. Maternal urine of all patients was examined at 12, 16 and 20wks’ gestation for the SRY gene (sex-determining region Y) as a cffDNA (cell free fetal DNA) marker and Ribonuclease P RNA component H1 (RPPH1) as a total cfDNA (cell free DNA) marker using a quantitative real-time PCR assay. Results: SRY gene was detected in maternal urine of those pregnant with male fetuses starting from 16weeks in 25% (20/80) of cases only and in 80% of cases (64/80) at 20weeks, but it was not detected at 12weeks. All women female fetuses were negative for SRY gene. Conclusions: Cell free fetal DNA in maternal urine was not detected in early gestational age using SRY gene alone despite the use of extraction kit specific for extraction of Free-circulating nucleic acids and highly sensitive reported PCR technique. Further studies should be done to evaluate whether cell free fetal DNA in maternal urine can be detected after reaching a certain threshold in blood.