The Application Of Tn5 Transposase In Abortion Tissue Genetic Testing

As the increasing application scenarios of NGS technology,more and more NGS based technology has been applied in clinical testing area,such as NIPT(Non-invasive prenatal testing)for Down Syndrome,genetic testing for hereditary cancer and pre-implantation genetic diagnosis/screening(PGD/PGS)for in vitro fertilization,and so forth.Nowadays,detection of chromosomal abnormalities in abortion tissues is in urgent demand,especially for those couples with repeated-abortion histories from unknown causes.With the NGS based detection technology for chromosomal abnormalities of those abortion tissues,it can uncover the leading reason of the abortions and then make it possible to further design and carry out personal pregnancy guidance for those couples.As the increasing application scenarios of NGS technology,library construction method has also been developed by leaps and bounds with more and more library construction approaches being available.For commercial companies and clinical institutes who provide NGS based chromosomal abnormality detection services,the library construction method requires characteristics of not only the reliability but also the fast turnaround time and the low sample inputs.In this study,we focus on the enzymatic fragmentation library construction method and evaluate its feasibility in the chromosome abnormality detection for abortion tissues.The enzymatic fragmentation library construction technology uses the Tn5 transposase for both DNA fragmentation and adapter ligation,which,compare to traditional mechanical fragmentation method,enables short turnaround time and ultra-low input DNAs and as a result,is widely used in various applications.In this study,62 libraries from 26 abortion tissues libraries were constructed using the Tn5 transposase(Vazyme Biotech Co.,Ltd),and sequenced on Ion Proton platform(Life Technology Corp).During the library preparation,we tested five key experimental parameters including amount of DNA inputs,transposase version,enzyme reaction time,size selection using AMPure XP beads and library quantification methods.All conducted parallel comparison to their corresponding outcomes generated using canonical library construction method and Hi Seq platform based test.Our results showed that,in combination with the Ion Proton sequencing platform,based on Tn5 transposase library construction method,it can deliver reliable chromosomal abnormality detection with faster turnaround time and less DNA inputs.In addition,this study provides valuable data and guidelines in further optimization of library construction parameters and will pragmatically facilitate the clinical chromosomal abnormality detection for the abortion tissues.