Objective: Long non-coding RNAs (lncRNAs) are emerging as novel biomarkers for a variety of chronic conditions including autoimmune disease. PAXgene Blood RNA tubes are routinely used in clinical research and molecular diagnostic development to capture RNA profiles in peripheral whole blood. While the stability of mRNA expression profiles captured using PAXgene tubes has been documented previously, no previous work has determined the stability of lncRNA expression profiles observed in PAXgene tubes stored at - 80 °C. Here we sought to determine the effects on lncRNA expression profiles following - 80 °C storage of total RNA templates, cDNA synthesized using fresh or frozen total RNA template, and the impact of freeze-thaw cycles on both total RNA and cDNA obtained from PAXgene tubes.
Results: We find that storage of whole blood in PAXgene tubes, total RNA and cDNA for up to 1 year at - 80 °C or up to ten total RNA or cDNA freeze-thaw cycles do not significantly alter lncRNA expression profiles compared to baseline. As monthly expression profiles were determined, some month to month lncRNA expression variability was observed. However, all monthly observations fell within the 95% confidence interval calculated at baseline.
Keywords: Long non-coding RNA; Messenger RNA; Multiple sclerosis; PAXgene blood RNA tube; Quantitative real time PCR; Storage.