Abstract 4932: Development of a highly sensitive library prep method for identifying pathogenic variants from FFPE tumor samples

Abstract

Abstract The application of genomics in cancer has led to an improved understanding of the disease. To date, 125 known driver genes have been discovered*. These genes and their pathways have become the focus of small-molecule drug development. While the number of available targeted therapies is limited, an estimated 800 oncology drugs are in development*, many of which target specific mutations. Single-analyte companion diagnostics exist for the approved therapies, and more might be developed as new therapeutics become available, but the need to assay each variant individually can be ineffective.. An additional, well-known challenge is the degradation and damage caused to DNA in formalin-fixed, paraffin-embedded (FFPE) samples. For these reasons, Illumina is developing a novel method for simultaneous detection of multiple somatic variants from FFPE specimens. This method leverages a multiplexed PCR approach with amplicons designed to a 15-gene panel that can detect somatic variants in 14 genes, and copy number changes in 3 genes. In our experiments, this multiplexed PCR assay has been demonstrated to be highly sensitive, yielding results from as little as 20 ng of DNA extracted from FFPE tissue, even if the DNA is highly damaged and degraded. Somatic variants can be detected down to 5% allele fraction, and gene amplifications can be detected for ≥ 2.2-fold change in copy number. This method, incorporating newly designed software, will be deployed as part of the Illumina Universal Oncology Test System on the MiSeqDx™ (under development), analyzing the sequencing results, and generating reports of mutations and copy number changes in cancer samples. Citation Format: Amanda G. Young, Charles Lin. Development of a highly sensitive library prep method for identifying pathogenic variants from FFPE tumor samples. [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 4932. doi:10.1158/1538-7445.AM2015-4932