A New Method Of The Library Construction Used In The Noninvasive Prenatal Testing

The rapid development of high-thro?ghput sequencing technology makes the research of genomics enter a new period and the understanding about genomics of the molec?lar biological scientists rise to a new level.Meanwhile,the technology is increasingly significant in clinical application.The accuracy of the noninvasive prenatal diagnosis has been identified after several years of development.Now it is gradually accepted by doctors and people.With the costs of high-thro?ghput sequencing continue to reduce and the profit is becoming smaller,reducing the ex periment cost to increase the profit is one of the major driving forces that promote the development of the industry.The effective method is to simplify the experiment process so that improve the stability of the experiment operation and reduce the probability of error.Based on the Illumina sequencing platform,this paper established a new method to construct the library used in the noninvasive prenatal diagnosis.We developed the beads purification buffer which can make the nucleic acid bind to the beads and optimize the experimental process.The enzyme reaction acted with the beads.The beads purification buffer was added to purify the nucleic acid after enzyme reaction.This process didn't need add new beads.It made the entire library construction finish in one tube avoiding frequently transferring tubes.This method reduced the beads,which approximately accounted for the third of the cost in the library construction.It co?ld effectively cut down on the cost of library construction and as well as decrease the three times of tranferring tubes,which reduced the possibility of the cross-contamination and sample confusion led by transferring tubes.In addition,it also shortened the experiment time(approximately 30 min).The new method made a comparation with the traditional library construction method and parallelly tested 140 peripheral blood samples of pregnant women.The concentration of library reached 25.4-63.8ng/?l and the success rate were 100%,which verified the well stability of the method.Furthermore,the data quality was obviously improved.The concentration of cell-free fetal DNA compared with the same sample increased 1.52% on average,which contributed to enhancing the abnormal chromosome signal and increasing the detection sensitivity.The average GC content of the traditional method was 39.87% and the new method was 40.32%,which was closer to the average level of human gene.In summary,the new method had less cost and shorter operation time.The overall performance was superior to the traditional method,which had a great prospect in the application of the library construction.