Formalin-fixed, paraffin-embedded (FFPE) samples are preserved tissue samples that are generally associated with disease. Many of these samples represent clinical outcomes, which could provide a potential gold mine of information when linked with underlying expression profiles. FFPE samples generally contain partially degraded RNA, so transcription analysis is a challenge for many gene expression assays. By using unique PCR and labeling steps based on the proven GoldenGate chemistry, Illumina's DASL assays provide high-quality data from degraded RNA samples. The DASL assay is available in the Whole-Genome DASL Assay, a fixed content, whole-genome profiling panel.

Whole-Genome DASL Assay

Covering more than 29,000 transcripts, the Whole-Genome DASL HT Assay is ideal for high-multiplex whole-genome profiling from FFPE samples. The assay combines the unique PCR and labeling steps of the original DASL assay with gene-based hybridization and the whole-genome probe set of Illumina's Direct Hybridization Assay. The product delivers high sensitivity and highly reproducible results from as little as 10–100 ng total RNA from fresh-frozen tissue or 50–200 ng total RNA from FFPE samples. The Whole-Genome DASL HT Assay obtains high concordance with qPCR at a low per sample cost compared to other methods.