Noninvasive Prenatal Diagnosis by Analysis of Fetal DNA in Maternal Plasma - Clinical Applications of PCR - page 107

5. Alternative calibrant materials, such as synthetic oligonucleotides ( 34 ) or plas-

mid with inserts of targeted genes ( 35 ) , have also been reported.

6. The protocol focuses on the use of real-time quantitative PCR for fetal DNA

detection in maternal plasma. However, other assay platforms have also been
adopted for fetal DNA detection, including conventional PCR, which is less sen-
sitive ( 3 ) ; and mass spectrometry, which has both superior sensitivity and speci-
ficity ( 36 ) .

7. Many groups perform triplicate analyses ( 30 , 37 ) , and it has been reported that

analytical results can be interpreted with greater confidence when higher number
of replicates are performed ( 38 ) .

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