Two approaches for calculating female fetal DNA fraction in noninvasive prenatal testing based on size analysis of maternal DNA fragments

[摘要] The concentration of cell-free fetal DNA fragments should be detected before noninvasive prenatal testing(NIPT). The fetal DNA molecules have significant clinical potential in determining the overall performance of NIPTand clinical interpretation. It is important to measure fetal DNA fraction before NIPT. However, there is still littleresearch on how to calculate the concentration of female fetuses. Two estimation approaches were proposed tocalculate fetal DNA fraction, including the fragments size-based approach, aneuploid-based approach, which are allapproaches based on chromosome segments. Based on high-throughput sequencing data, two approaches to calculatethe DNA fraction of male fetuses were tested and obtained the experiment values, which were close to the actualvalues. The correlation coefficient of fragments size-based approach was 0.9243 (P < 0.0001) and the aneuploid-basedapproach reached 0.9339 (P < 0.0001). We calculated the concentration of female fetuses and obtained remarkableexperimental results. We came up with two approaches for calculating the fetal DNA fraction of female fetuses. Itprovides an important theoretical basis for the detection of female fetal concentration in future clinical diagnosis.

[学科分类] 仪器

[关键词] Fetal DNA fraction;Noninvasive prenatal testing;Cell-free fetal DNA;Female fetus