NIPT

Quantitative real-time PCR (qPCR)

 

1. Methylation specific digestion (fragmentation) of maternal DNA

Trisomy 21 negative image

Trisomy 21 positive image

image hypermethylated fetal DNA region on chromosome 21

image hypermethylated fetal DNA region on reference chromosome

image hypomethylated maternal and fetal DNA region on chromosome 21 and reference chromosome

 

2. Multiplex qPCR for measurement of fetal DNA on chromosome 21

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Probes with fluorescent dyes bind to defined gene regions of chromosome 21
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Probes with fluorescent dyes bind to defined gene regions of the reference chromosome