Objective: 1- Fetal Down syndrome detection by QF technique - PCR. 2- Review of technical value QF - PCR in prenatal diagnosis of Down syndrome. Subjects and Methods: Consists of 90 samples of amniotic fluid of pregnant women with high-risk technical analysis by QF-PCR method to control culture and cytogenetic analysis. Results: Already detected 26/90 cases of trisomy 21. In 01 cases, induding 21 and 21 chromosome translocation in collaboration with genetic celts diagnosis. There are 01 cases of complex translocation 47, XX, +21, t (1, 3, 21) (P22
q11.2
p13) QF-PCR technique correctly identified Down syndrome (DS) that genetic cells doubt. Conclusion: Application of technical success QF-PCR in the diagnosis of DS subjects Biomedical - Genetics, Center for Genomic Research - Protein Hanoi Medical University, Military Medical Academy and diagnostic centers before birth Central Maternity Hospital. Using techniques QF-PCR for accurate results 100 percent of trisomy 21 cases. Coordinate with cytogenetic techniques accurately detect the translocation DS cases that genetically engineered celts doubt.