Fig. 1: Differences and characterization in circRNA expression profiles between IDD and normal NP tissues.

a Volcano plots are used for visualizing differential expression between two different conditions. The horizontal lines correspond to 2.0-fold (log2 scaled) up and down, respectively, and the vertical line represents an adjusted P value of 0.05 (−log10 scaled). The red and green points represent the upregulated- and downregulated-expressed circRNAs, with statistical significance. b Hierarchical cluster analysis of the significantly upregulated and downregulated circRNAs. Each column represents a sample and each row represents a circRNA. Red represents high relative expression and green represents low relative expression. c RCircos image showing human chromosome representation with data tracks for connectors, differentially expressed circRNA labels, heatmap of all circRNAs (red and green represent the upregulated and downregulated circRNAs compared with normal NP tissues), scatter plot of all circRNAs, line plot of all circRNAs, and histogram of significantly differential expressed circRNAs. d Constituent ratios of differentially expressed circRNAs