Clinical Evaluation Of Rapid Prenatal Detection Of Aneuploid Abnormalities With Multiplex Ligation-dependent Probe Amplification

Objective： To explore the application of multiplex ligation-dependent probeamplification (MLPA) for rapid detection of aneuploid abnormalities in prenata ldiagnosis.Methods：From October2009to December2010, amniotic fluid samples werecollected during17-24weeks’ gestation from1229pregnant women whose fetuseswith high risk of Down’s syndrome screened by serum biochemical markers. inPrenatal Diagnosis Center of Shenzhen Maternity and Child Healthcare Hospital.DNA was extracted from5ml uncultured amniotic fluid and detected for aneuploidyabnormalities of chromosome X, Y,13,18, and21by MLPA. Meanwhile, amnioticcells were cultured for G-band chromosome karyotyping from15ml amniotic fluid.The results from two different methods were compared to confirm the sensitivity andspecificity of MLPA.Result：G-band karyotyping analysis showed586normal male and596normal femaleeuploidies,38chromosome X, Y,13,18, and21aneuploidies abnormalities (34nonmosaic aneuploidies and4mosaic aneuploidies).Compared to G-band karyotyping,MLPA analysis had the same results except unable detecting2cases of mosaicaneuploidies. MLPA achieved100%sensitivity and100%specificity in detectingnonmosaic aneuploidies of21,18,13, X and Y chromosome.27chromosomestructural abnormalities including inversion, translocation, duplication and one case of marker chromosome were also detected by G-band karyotyping analysis. MLPA couldnot dectect these structural abnormalities due to there being no copy number changeor no probes mached to corresponding sites of chromosome.Conclusion：1. The sensitivity and specificity for detecting the nonmosic aneuploidiesof chromosomes X, Y,13,18and21by MLPA were100%. MLPA is an efficient andreliable method for rapid detection of aneuplodies.2. MLPA is characteried by rapidness; high throughputand is suitable forprenatal aneuploidy detection.