%0 Journal Article
%T Multiple z-Score Based Method for Noninvasive Prenatal Test Using Cell-Free DNA in Maternal Plasma
%A Hyuk Jung Kwon
%A Amit Goyal
%A Heesu Im
%A Kichan Lee
%A Seon Young Yun
%A Yoon Hee Kim
%A Sungjong Lee
%A Mi-Gyeong Lee
%A Hyuna Lee
%A Reena Garg
%A Boram Park
%A Soyoung Choi
%A Joungsu Joo
%A Jin-Sik Bae
%A Min-Jeong Kim
%A Min Seob Lee
%A Sunghoon Lee
%J Open Journal of Genetics
%P 1-8
%@ 2162-4461
%D 2017
%I Scientific Research Publishing
%R 10.4236/ojgen.2017.71001
%X <strong>Objective:</strong> To improve the detecting accuracy of chromosomal aneuploidy of fetus by non-invasive prenatal testing (NIPT) using next generation sequencing data of pregnant womenĄŻs cell-free DNA. <strong>Methods:</strong> We proposed the multi-Z method which uses 21 z-scores for each autosomal chromosome to detect aneuploidy of the chromosome, while the conventional NIPT method uses only one z-score. To do this, mapped read numbers of a certain chromosome were normalized by those of the other 21 chromosomes. Average and standard deviation (SD), which are used for calculating z-score of each sample, were obtained with normalized values between all autosomal chromosomes of control samples. In this way, multiple z-scores can be calculated for 21 autosomal chromosomes except oneself. <strong>Results:</strong> Multi-Z method showed 100% sensitivity and specificity for 187 samples sequenced to 3 M reads while the conventional NIPT method showed 95.1% specificity. Similarly, for 216 samples sequenced to 1 M reads, Multi-Z method showed 100% sensitivity and 95.6% specificity and the conventional NIPT method showed a result of 75.1% specificity. <strong>Conclusion:</strong> Multi-Z method showed higher accuracy and robust results than the conventional method even at low coverage reads.
%K Cell-Free DNA
%K z-Score
%K Multiple Thresholds
%K Coefficient of Variance
%K Noninvasive Prenatal Testing
%K NIPT
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=73977