Absence of fetal cells in maternal circulation at a level of 1 in 25,000.
A dual polymerase chain reaction (PCR) technique is developed which enables the detection of one part male DNA in 25,000 parts female DNA. The technique amplifies a part of the X-Y homologous amelogenin gene in which the Y counterpart has a 189 bp deletion within one of the introns. This deletion has made it possible to identify individual X and Y counterparts based on the difference in size between them. None of the 18 pregnant women studied showed a positive Y-signal although eight of them bear male fetuses excluding the presence of fetal cells at one in 25,000 maternal cells. The results presented here show that a sensitivity of greater than one in 25,000 is required for detection of fetal genetic disease using maternal peripheral blood.
Nakagome
Y
Y
Department of Congenital Abnormalities Research, National Children's Medical Research Center, Tokyo, Japan.
Seki
S
S
Nagafuchi
S
S
Nakahori
Y
Y
Sato
K
K
D001483:Base Sequence; D001775:Blood Circulation / Q000502:physiology*; D002452:Cell Count; D004247:DNA / Q000302:isolation & purification*; D005260:Female; D005333:Fetus / Q000166:cytology*; D006801:Humans; D008431:Maternal-Fetal Exchange / Q000502:physiology*; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D014998:Y Chromosome
D004247:DNA