Next-generation sequencing of double stranded RNA is greatly improved by treatment with the inexpensive denaturing reagent DMSO

Double stranded RNA (dsRNA) is the genetic material of important viruses and a key component of RNA interference-based immunity in eukaryotes. Previous studies have noted difficulties in determining the sequence of dsRNA molecules that have affected studies of immune function and estimates of viral diversity in nature. Dimethyl sulfoxide (DMSO) has been used to denature dsRNA prior to the reverse transcription stage to improve RT-PCR and Sanger sequencing. We systematically tested the utility of DMSO to improve sequencing yield of a dsRNA virus (Φ6) in a short-read next generation sequencing platform. DMSO treatment improved sequencing read recovery by over two orders of magnitude, even when RNA and cDNA concentrations were below the limit of detection. We also tested the effects of DMSO on a mock eukaryotic viral community and found that dsRNA virus reads increased with DMSO treatment. Furthermore, we provide evidence that DMSO treatment does not adversely affect recovery of reads from a single-stranded RNA viral genome (Influenza A/California/07/2009). We suggest that up to 50% DMSO treatment be used prior to cDNA synthesis when samples of interest are composed of or may contain dsRNA.