[Development of multiple quantitative fluorescent PCR for rapid diagnosis of common aneuploidy and it's clinical application].

ABSTRACT

In this study we have established a technique of multiple quantitative fluorescent polymerase chain reaction (QF-PCR) for prenatal diagnosis of common chromosomal abnormality using multiple short tandem repeat markers (STR-marker) on chromosomes 21 and 18 with the DNA samples from 20 cases of Down's syndrome, 3 cases of trisomy 18 and 40 cases normal controls. The technique established was applied in prenatal diagnosis in 165 clinical cases and 4 cases of newborn infants with digestive tract obstruction. The result this technique was compared with the results of karyotyping. Four cases of trisomy 21 and 1 case of trisomy 18 were identified among 169 samples, which was completely concordant with the results of karyotyping. All clinical samples were diagnosed in 1-3 days without misdiagnosis and missed diagnosis. Five cases were diagnosed by QF-PCR only due to the failure of karyotyping. Twenty-two cases of fetuses with structure malformation indicated by B-ultrasonography were subjected to karyotyping. One case of 45, X and 1 case of 47, XXY were identified. In conclusion, QF-PCR technique is rapid and accurate for the detection of trisomy 21 and trisomy 18. It is suitable for prenatal diagnosis of common chromosomal abnormality for pregnant women with advanced ages who were identified as having a high risk by serum screening. QF-PCR technique combined with karyotyping can provide better service for clinical demanding of prenatal diagnosis.