Sensitivity of DCSR3/GAPDH ratio using quantitative real-time PCR in the rapid prenatal diagnosis for down syndrome

Background: Down syndrome, the most common birth defect, is caused by trisomy 21. The aim of this study was to investigate whether quantitative real-time PCR can be used as a sensitive technique for prenatal diagnosis of Down syndrome.

Methods: We used a quantitative real-time PCR technique to measure the gene dosage of the Down syndrome critical region (DSCR3) by calculating the ratio of DSCR3 to GAPDH using standard curves. Sex-determining region Y was simultaneously detected by real-time PCR to identify the sex of the fetus.

Results: The DSCR3/GAPDH ratio of the trisomy 21 fetus samples and that of normal controls was 0.72 +/- 0.34 and 0.54 +/- 0.18, respectively.

Conclusion: In this study, there was no significant difference in the DSCR3/GAPDH ratio between the fetal and peripheral blood DNA samples of trisomy 21 fetuses and those of normal controls.