Study On Prenatal Diagnosis Using Both Karyotyping And BoBs

Objective:To establish and to evaluate a new model of prenatal diagnosis of fetal chromosome aneuploidy abnormality and common chromosome microdeletion syndrome by using both Bo Bs and karyotyping.Methods:Bo Bs is a new technology for rapid prenatal diagnosis.Diagnosing Chromosome aneuploidy abnormality(13,18,21,X and Y chromosomes)and 9 microdeletion syndromes by extracting the DNA samples from the human body specimens,hybridizing the designed probe with the target region of the gene.From November 2011 to October 2016,pregnant women accept invasive prenatal diagnosis in Fujian Province Maternal and Child Health Hospita using karyotyping and Bo Bs technology at the same time,to diagnose the fetal chromosomal abnormalities and 9 chromosomal microdevelopment prenatally,then follow-up pregnancy outcomes.Results:Bo Bs detects a batch two working days.In 522 samples,Bo Bs successfully detected Twenty-one cases of T21,6 cases of T18,1 case of sex chromosome aneuploidy,2 cases of chimera(45,X [9] / 46,XY [105],47,XX,+ 21 [47] / 46,XX,[52]).In 21 cases of abnormal samples,20 cases were Consistent with karyotyping results,except for one case of T18 karyotyping failed(due to failure of cell culturing,confirmed by QF-PCR.Five cases of chromosome microdeletion syndrome were detected by Bo Bs technique,including 3 cases of Di George syndrome type 1,1 case of Prader-Willi syndrome and 1 case of 22q11 microduplication.The cases of chromosome microdeletion and microduplication were comfirmed by QF-PCR Or SNP-array.The 22q11 microduplication inherited from his mother was verified.So she choose to continue pregnancy,then fertility normal fetus.After genetic counseling,the remaining 25 pregnant women have chosen to terminate the pregnancy.Karyotyping takes 2 weeks to detect a batch,discovering 13 chromosomal abnormal cases Bo Bs missed,including 8 case of chromosome inversion and 5 cases of chromosome translocation.Among 13 missed cases,11 cases were inherited from parents and 2 cases were mutations.After genetic counseling,all 13 pregnant women are selected to continue pregnancy,then fertility normal fetus.Karyotyping discover a case of chimera(46,X,+ mar [86] / 45,X)Bo Bs did not discover.After genetic counseling,the pregnant woman chose to terminate the pregnancy.Conclusion:1.Bo Bs is a rapid,simple and reliable prenatal diagnosis technique for detecting chromosomal aneuploidy abnormalities and nine common microdeletion syndromes.2,This diagnositic technology is not used for the low proportion of chimera,the abnormal chromosomal regions of amplification and deletion,point mutation,balanced rearrangements,ploidy variation,uniparental disomy and methylation alterations probes not covered with.3,Bo Bs can enhance the detection rate of chromosomal abnormalities,especially the pregnant women with the high serum screening risk,advanced-age,abnormalities of fetal ultrasound.4,Combined use of karyotyping and Bo Bs,is a rapid and effective prenatal diagnosis model that may enlarge our horizon on chromosomal diseases and should be widely used in future clinical service.