[Detection of fetal DNA in maternal plasma using the nested polymerase chain reaction].
OBJECTIVE
To search for a new method of non-invasive prenatal gene diagnosis.


METHODS
A single-copy human DYS14 gene of Y-chromosome of fetal DNA sequence was amplified by nested polymerase chain reaction (PCR) from twelve pregnant maternal plasma (12-40 weeks). A 239 bp and 198 bp specific fragment were obtained. The maternal plasma samples of twelve pregnant women were used directly for nested PCR. RESULTS The fragment was identified in 8 of 10 male-bearing pregnant women plasma. The diagnostic accordance rate was 80% (8/10), 6 to 8 women gave positive signals in two consecutive amplifications, 2 of 8 women gave positive signals in the second amplification. The rate of positive was increased greatly by nested PCR (from 60% to 80%). None of the other 2 female-bearing pregnant women had positive results. The final accuracy of 83.3% (10/12) was attained in all cases.


CONCLUSIONS
The finding of circulating fetal DNA in maternal plasma may have new implications for non-invasive prenatal gene diagnosis, and the nested PCR possesses the advantages of sensitivity and specificity which improves the clinical application.
Second Affiliated Hospital, Harbin Medical University, Harbin 150086.
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H
Chi
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Kang
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Hu
D000328:Adult; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis / Q000235:genetics*; D005333:Fetus; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods; D011247:Pregnancy / Q000097:blood* / Q000235:genetics; D011296:Prenatal Diagnosis / Q000379:methods*; D017422:Sequence Analysis, DNA; D014998:Y Chromosome