[Detection of fetal SRY gene in maternal plasma by real-time fluorescence quantitative PCR].
OBJECTIVE
To isolate fetal DNA from maternal plasma and examine its fetal origin.


METHODS
Fetal DNA in maternal plasma was isolated from 150 samples in the first trimester and mid-trimester of pregnancy, respectively. Real-time fluorescence quantitative polymerase chain reaction PCR (FQ-PCR) was used to determine sex-determining region Y (SRY) gene on Y chromosome.


RESULTS
Eighty-two women in the first trimester and 90 women in the mid-trimester carried male fetuses,70 and 90 samples of them were positive, respectively. The mean concentrations were (58.82+/-20.90) copies/ml and (152.08+/-62.61) copies/ml. The results of FQ-PCR were negative in the women who carried female fetuses.


CONCLUSIONS
The results show that fetal SRY gene can be found at a time as early as 42 days of gestation in maternal plasma by the use of FQ-PCR. The number of fetal DNA increases with gestational age. The real-time FQ-PCR is of great value in the non-invasive prenatal diagnosis.
Tianjin Central Hospital of Obstetrics and Gynecology, Tianjin, 300052 PR China. rccxqy@sina.com.cn
Chen-chun
CC
Ren
Wen-jing
WJ
Wang
Guo-chuan
GC
Liu
Hai-xia
HX
Zhang
Yue-fan
YF
Xu
Zhi-ming
ZM
Tang
Li-ling
LL
Yang
Pei-jia
PJ
Chen
Bin
B
Li
D000328:Adult; D004247:DNA / Q000097:blood / Q000235:genetics* / Q000302:isolation & purification; D005260:Female; D005333:Fetus / Q000378:metabolism; D005453:Fluorescence; D005865:Gestational Age; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods*; D011247:Pregnancy; D011264:Pregnancy Trimesters; D051876:Sex-Determining Region Y Protein / Q000235:genetics*
D051876:Sex-Determining Region Y Protein; D004247:DNA