Abstract 4894: Targeted sequencing of myeloid cancers using single-molecule enrichment in picodroplets

Abstract

Abstract A new method for enrichment of targeted genomic regions for next generation sequencing (NGS) is the use of single-molecule formatted PCR amplification, with the sample's target DNA partitioned into uniform picoliter volume droplets such that there are either zero or one target molecule in each droplet. All the droplets contain all of the primers and PCR reagents, ensuring that every target molecule from the sample is amplified, minimizing the amount of input required. Endpoint PCR using this single molecule format results in highly uniform yields that facilitate efficient use of the sequencing platform. In addition, the primers contain ‘Illumina tails’ that enable easy sample indexing and a workflow for loading directly onto a MiSeq without additional library preparation. Here we detail the use of this method with the ThunderBolts Myeloid Cancer Panel, which targets ∼550 commonly mutated regions in 49 genes implicated in the causation, prognosis, and recurrence of myeloid disorders. The panel targets include an expert-curated set of 16 full genes and 33 mutational hotspot regions, including challenging targets such as CEBPA and NOTCH1. We present results showing sample inputs as low as 10 nanograms (no pre-amplification used) provide sequencing metrics with 100% coverage at >100x depth (>95% at >500x depth) with a normalized mean read depth of 2500x and high uniformity (>90% of amplicons within 0.2x of the mean), enabling detection of low minor allele frequencies (<5%). The workflow is easy and rapid, with <2 hours hands-on time and sample-to-results in <48 hours. In addition, we demonstrate similar performance metrics when adding additional primer pairs (ThunderBolts PLUS), ensuring continued flexibility for researchers to use the core panel plus additional key targets as they are identified and validated. In summary, the ThunderBolts Myeloid Cancer Panel shows excellent sequencing coverage, high read depth and uniformity, and detection of low frequency mutations implicated in myeloid cancers. Starting from low input DNA samples, the workflow is easy and fast, enabling low cost targeted Illumina NGS sequencing with an expert curated panel that provides flexibility for expansion. Citation Format: Michael L. Samuels, Steve K. Kotsopoulos, Frances Long, Holly Gettler, Omo Clement, Jeff Olson. Targeted sequencing of myeloid cancers using single-molecule enrichment in picodroplets. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4894. doi:10.1158/1538-7445.AM2015-4894