Abstract 1330: Scalable single-day workflows for variant calling with the Genexus Integrated Sequencer

Abstract

The purpose of this study is to test the speed, scalability, and flexibility of variant detection with the Genexus Integrated Sequencer. This research use only instrument uses nucleic acid input and executes the steps of library preparation, sequencing, analysis, and variant calling. Taking advantage of the instrument's flexibility in sample plexy, the authors used the Oncomine™ Comprehensive Assay v3 and commercially available control samples to detect SNPs, InDels, and fusions reliably at up to 6-plex paired DNA and RNA samples. The instrument can accommodate 1, 2, 4, or 6 paired DNA and RNA samples when using 1, 2, 3, or 4 lanes of the GX5 chip. Regardless of the number of samples analyzed, the system achieved at least 98% sensitivity, 98% positive predictive value, 95% agreement to known truth for de novo variants, and 98% agreement to known truth for hotspot variants in the Acrometrix™ Oncomine Hotspot Control. Also regardless of sample plexy, the system achieved at least 97% agreement to known truth for Fusions within the SeraSeq® Fusion RNA Mix v3. The flexible workflows allow for fast turn-around times of as little as 18 hours for a single sample pair and less than 30 hours for 6 paired DNA and RNA samples. Stability of system initialization is an important feature for flexible use of an NGS system, and read length is a limiting performance metric for evaluating stability. In order to test the Genexus system's read length and stability features the Oncomine™ TCR Beta-LR Assay GX was used. Instruments were initialized with sequencing consumables and tested for performance on day 1 and day 15. There was no statistically significant difference in total reads (3.5 ± 1.0 M at day 1 vs. 3.1 ± 1.0 M at day 15), the fraction of reads that are low quality reads (13% ± 2% vs. 14% ± 2%), or mean read length (301 ± 6 bases vs. 296 ± 6 bases) between the two time points. In conclusion, the Genexus integrated sequencer is a robust NGS system that facilitates rapid turn-around time, flexibility in sample plexy, and stability in system consumables use. Citation Format: Jason Gioia, Iris R. Casuga, Frances Chan, James Commins, David Conners, Marla Kratzer, Collyn Seeger, David Yaccarino. Scalable single-day workflows for variant calling with the Genexus Integrated Sequencer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1330.