Fetal gender determination in early pregnancy through qualitative and quantitative analysis of fetal DNA in maternal serum.
Fetal DNA in maternal plasma and serum has been shown to be a useful material for fetal gender determination and for screening tests for abnormal pregnancies except during early gestational ages. Maternal serum samples were obtained from 81 pregnant women during the 5th-10th weeks of gestation. Fetal gender was determined by conventional polymerase chain reaction (PCR) to detect a Y-chromosomal sequence (DYS14) in maternal serum during early gestation and confirmed by examination of the newborns after delivery. Real-time quantitative analyses of the SRY and beta-globin genes were also performed in order to determine fetal gender and to quantify fetal DNA concentration in maternal serum during early gestation. When using conventional PCR, the total sensitivity of identifying a male fetus was 95%, but its sensitivity after the 7th week was 100%, whereas in real-time quantitative PCR, the total sensitivity after the 5th week was 100%. Quantitative analyses of the SRY gene revealed that the mean concentration of fetal DNA in maternal serum was 30.55 copies/ml, that fetal DNA concentration showed a tendency to increase with the progression of pregnancy, and that it had a wide normal range. Thus, we could confidently determine fetal gender by using maternal serum samples taken as early as the 7th week.
Honda
Hiroshi
H
Department of Obstetrics and Gynecology, Hiroshima University School of Medicine, 1-2-3, Kasumi, Minami-ku, Hiroshima 734-8551, Japan. honda@mcai.med.hiroshima-u.ac.jp
Miharu
Norio
N
Ohashi
Yoko
Y
Samura
Osamu
O
Kinutani
Masayuki
M
Hara
Tetsuaki
T
Ohama
Koso
K
D004247:DNA / Q000097:blood / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics*; D036861:Delivery, Obstetric; D004622:Embryo, Mammalian; D005260:Female; D005333:Fetus; D005865:Gestational Age; D005914:Globins / Q000235:genetics; D006801:Humans; D007231:Infant, Newborn; D009687:Nuclear Proteins; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D011261:Pregnancy Trimester, First / Q000235:genetics*; D012044:Regression Analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019849:Sex Determination Processes; D051876:Sex-Determining Region Y Protein; D014157:Transcription Factors; D014998:Y Chromosome
D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; C497745:SRY protein, human; D051876:Sex-Determining Region Y Protein; D014157:Transcription Factors; D005914:Globins; D004247:DNA