Clinical Performance Of High-throughput Sequencing Technology In Prenatal Diagnosis

Purpose There is a high incidence of fetal birth defects in China which brings mental and economy stress to the family.How to reduce the birth defects is a hot topic in recent years.Prenatal diagnosis is a method of predicting genetic defects and congenital malformations by using modern biology,biochemistry,immunogenetics,cytogenetics,molecular genetics and other technologies.In recent years,with the pregnant women’s eugenics and childbearing awareness continues to strengthen,China’s prenatal diagnosis of medical resources is becoming more and more serious.It is important to seek a safe,simple,economical and practical prenatal screening and diagnostic method to reduce the birth defects.The current clinical diagnosis and treatment of prenatal diagnosis is still far from the level of genetic diagnosis,which can not meet the clinical needs.With the reduction of sequencing cost,the rapid development of high generation sequencing(NGS)technology makes it possible to make it widely available.The rapid development of high-throughput sequencing technology will lead to the reform of traditional medical treatment model.The genetic information of the patients with reproductive abnormalities was analyzed by high-throughput sequencing technique.The genetic characteristics of the population were discussed at the molecular level,and the clinical application of the technique was discussed.This study was to establish a new model of reproductive medicine based on high-tech platform.At present,the clinical application of non-invasive prenatal testing technology which based on high-throughput sequencing technology is a new technology of prenatal screening.It detects the fetal free DNA in the peripheral blood of pregnant women,and detects the chromosome aneuploidy of the fetus 21、18、13.Previous experiments confirmed that the technology has a high sensitivity,specificity,but its impact to traditional invasive prenatal diagnosis technology needs to be further confirmed.With the improvement of people’s awareness of prenatal and postnatal care,there is an increasing demand for genetic testing of miscarriages.However,due to the traditional cytogenetic detection technology requires cumbersome cell culture process,manual operation links,the operating procedures are relatively complex.low detection resolution,the quality of the test and the technical level of the operator has a great relationship.With the increasing number of chromosomal microdefections,the clinical significance of microtransmitting is further confirmed,which may be one of the major causes of major birth defects such as neonatal birth developmental abnormalities and mental retardation.The traditional method of cell genetic diagnosis has been far from meeting the clinical need for the detection of birth defects.The establishment of a fast,accurate,and practical method of prenatal diagnosis has always been the goal pursued in this field.Chromosome genome copy number variation(CNVs)technology,gradually as a kind of fast,accurate,flexible and other characteristics of the new detection methods for clinical use of embryos and fetal prenatal testing,application in amniotic cells is still in research stage.Method In this study,6005 high-risk pregnant women who were admitted to Tangshan Maternal and Child Health Hospital from January 2012 to January 2014 were selected as the subjects.All subjects were divided into two groups before and after NIPT.Detection rate of 21-trisomy,18-trisomy and 13-trisomy were compared between the two groups.The sensitivity,specificity,false positive rate and positive predictive value of NIPT were analyzed.The clinical application value of this technology was evaluated.From June 2015 to December 2015,the prenatal diagnosis center of Maternal and Child Health Hospital of Tangshan City was diagnosed as the clinical application data of CNVs technology in the diagnosis of abortion villi were analyzed.The clinical application value of the technique was evaluated.The feasibility of this technology was discussed.From June 2015 to December 2015 data of CNVs and amniotic fluid chromosomal analysis were analyzed in Tangshan City Maternal and Child Health Hospital.The clinical application of this technology was discussed.This study provides a scientific basis for the further establishment of the new technology.Results1.Compared with the traditional scheme of prenatal diagnosis,combined NIPT prenatal diagnosis scheme makes more pregnant women can accept further prenatal testing,pregnant women give up further prenatal diagnosis decreased significantly(81.0%vs13.9%,p<0.001),statistically significant difference;Combined NIPT prenatal diagnosis scheme,21-trisomy,18-trisomy and 13-trisomy detection rate increased significantly(0.4%vs1.0%,p=0.01).NIPT detecting fetal 21,18,13 chromosomal aneuploidy with high sensitivity and specificity.For 21-trisomy,18-trisomy and13-trisomy,NIPT detection specific degree was 100%,99.9% and 99.9%,positive predictive value was 100%,83.3% and 50.0%,respectively and the false positive rate was 0%,0.04% and 0.04%.2.NGS-CNVs in the clinical application of genetic testing results show that the flow product NGS-CNVs and villus cell culture comparative karyotype analysis technology,NGS-CNVs detection rate significantly higher than that of karyotype analysis,difference was statistically significant(p<0.001).Villus cell culture,chromosome analysis can detect more balanced translocation chromosome,statistically significant difference,(p<0.001);Clinical application of NGS-CNVs technology to detect chromosome aneuploidy,the results consistent with fluff cultivate karyotype analysis.Compared with chromosome karyotype analysis,NGSCNVs detection can be found more chromosome abnormal microstructure,statistically significant difference,(p<0.001).3.NGS-CNVs detection in prenatal diagnosis of clinical application show that compared with amniotic fluid cells karyotype analysis technology,karyotype analysis can detect more balanced translocation,inversion between arm of chromosome structural abnormalities than NGS-CNVs.The data is statistically significant difference,(p<0.001);NGS-CNVs detected more chromosome abnormal microstructure,The difference have statistical significance,(p<0.001);By analysis CNVs and amniotic fluid puncture indications,according to the relationship between prenatal ultrasound abnormality is closely related to test positive for CNVs.Conclusion1.NIPT can quickly,non-invasive and accurate detect 21,18,13 chromosomal aneuploidy.It is more easily accepted by pregnant women.With NIPT as complement of traditional prenatal diagnosis,reasonable the technology combined with the existing technology of prenatal diagnosis,NIPT combined prenatal diagnosis scheme is feasible.NIPT combined prenatal diagnosis scheme,make more high-risk pregnant women participated in the further prenatal testing.NIPT does not affect the invasive prenatal diagnostic rate,at the same time detect more chromosome disease of children.By this way,it is more effectively to reduce the birth defects.NIPT combined prenatal diagnosis scheme is an economical and practical scheme.2.NIPT based on high-throughput sequencing technology,to check the fetus,18,21 and 13 chromosome aneuploidy with high accuracy.NIPT for testing 21-trisomy,18-trisomy and 13-trisomy sensitivity,specific degree were 100%,99.9% and 99.9%respectively,positive predictive value were 100%,83.3% and 50.0%,false positive rate were 0%,0.04% and 0.04%.3.NGS-CNVs detection used in the product flow,loss of amniotic fluid cells chromosome micro,micro repetitive genetic testing is feasible,can quickly and accurately find common chromosomal abnormalities,significantly shorten the test cycle.Detection of chromosomal aneuploidy results consistent with the results of karyotype analysis.NGS-CNVs can detection more abnormal microstructure and improve the level of genetic testing.NGS-CNVs found a large number of pathogenic unknown micro imbalances,its clinical significance remains to be further confirmed.By analysizing CNVs and amniotic fluid puncture indications,according to the relationship between prenatal ultrasound abnormality is closely related to test positive for CNVs.4.High-throughput sequencing in the field of prenatal screening and diagnosis of clinical application has a larger development space,with the traditional wool.Amniotic fluid cell culture,prenatal ultrasound,prenatal screening and diagnosis technology,combining can better play to the role of reducing birth defects.