Noninvasive Prenatal Screening for Common Fetal Aneuploidies Using Single-Molecule Sequencing

Amplification biases caused by next-generation sequencing (NGS) for noninvasive prenatal screening (NIPS) may be reduced using single-molecule sequencing (SMS), during which PCR is omitted. Therefore, the performance of SMS-based NIPS was evaluated. We used SMS-based NIPS to screen for common fetal aneuploidies in 477 pregnant women. The sensitivity, specificity, positive predictive value, and negative predictive value were estimated. The GC-induced bias was compared between the SMS-and NGS-based NIPS methods. Notably, a sensitivity of 100% was achieved for fetal trisomy 13 (T13), trisomy 18 (T18), and trisomy 21 (T21). The positive predictive value was 46.15% for T13, 96.77% for T18, and 99.07% for T21. The overall specificity was 100% (334/ 334). Compared with NGS, SMS (without PCR) had less GC bias, a better distinction between T21 or T18 and euploidies, and better diagnostic performance. Overall, our results suggest that SMS improves the performance of NIPS for common fetal aneuploidies by reducing the GC bias intro-duced during library preparation and sequencing.(c) 2022 United States & Canadian Academy of Pathology. Published by Elsevier Inc. All rights reserved.

Automated summary

Amplification biases caused by next-generation sequencing (NGS) for noninvasive prenatal screening (NIPS) can be reduced using single-molecule sequencing (SMS) without PCR. The performance of SMS-based NIPS was evaluated by screening for common fetal aneuploidies in 477 pregnant women. SMS achieved a sensitivity of 100% for trisomy 13 (T13), trisomy 18 (T18), and trisomy 21 (T21). Compared to NGS, SMS had less GC bias, improved distinction between T21 or T18 and euploidies, and better diagnostic performance.