Establishment A Genetic Diagnostic System For21/18/13/X/Y Chromosome Anueploidies By Multiplex Quantitative Fluorescence Polymerase Chain Reaction

Objectives Establishment of a genetic diagnostic system for21/18/13/X/Y chromosomeanueploidies by multiplex quantitative fluorescence polymerase chain reaction.Methods27makers were selected in this study, and averagely distributed on5chromosomes.There are eight makers on chromosome21(D21S2052, D21S1441,D21S1446, LFG21, D21S1435, D21S11, D21S1246and PentaD); six makers onchromosome18(D18S51, D18S535, D18S1002, D18S877, D18S851and D18S391); sixmakers on chromosome13(D13S256, D13S797, D13S317, D13S305, D13S800,D13S325); seven makers on gender chromosome, including three makers on Xchromosome(DXS9895, DXS6805, XHPRT)and one maker on Y chromosomal (SRY)andtwo makers on X and Y chromosomal(AMEL, ZFXY); X and the3rd chromosomeconsensus site is TAF9L. All27makers were amplificated in one tube. In this research itwas examed with500cases of normal samples,160cases of known karyotype analysis ofpositive samples and40high-risk of amniocyte. In accordance with the principle oframdom date table,40cases of amniotic fuild sampls were randomly selected from high-risk pregnant women in500normal samples, and with all40high-risk of amniotic fluidsamples were verified for the accuracy and reliability of the system.Results1QF-PCR results: The results of QF-PCR were obtained with24~48hoursafter samples collected.700samples (97.28%) were successfully analysed by QF-PCR.Among those500cases of normal samples,485were successed, and there are258casesof male,227cases of female. The40normal samples were analysised simultaneously byQF-PCR and karyotype analysis,38cases were turned out to be21,18,13, X, Y normalsamples,except2of those were unsuccessed. Among those160cases of known karyotypesamples, there are79cases of21-trisomy,73cases of XXY syndrome,5cases of18-trisomy,1case of13trisomy,1case of XYY syndrome,and1unsuccessed.The40cases of high-risk sample were successfully analysised by QF-PCR of37cases. Amongthose27cases were21,18,13, X, Y normal samples,10cases were trisomy21.2Karyotyping results: The results were obtanined2to3weeks after the80casessamples(91.25%) were collected. Among the73cases,10cases of trisomy21wereexamed.3The QF-PCR test is more rapidly and successfully. And no false positiveresult were found. Only a small cases of mosain and structural abromaloties cannot be detected.Conclusions The QF-PCR system were successfully established with the makersselected in this study of high polymorphism in Chinese population. And it is a simple,rapid and accurate detection method of chromosomal aneuploidy. It was the preferredmethod for non-integral rapid prenatal diagnosis and suitable for large-scale clinicalapplication. It will bring a great significance in improving the quality of births.