Fig. 3
Higher expression level in the intron-lost genes of C. elegans. The numbers of all annotated coding genes, intron-conserved genes, intron-lost genes, and intron-gained genes were 16,031, 677, 273, and 13, respectively. The FPKM value represents the gene expression levels, and the FPKM values equal to zero were removed. The FPKM values higher than 25 are not shown in the box charts. The p-values of Mann–Whitney U tests were 10−7 and 2 × 10−19, respectively. The small sample size makes comparing intron-gained genes with other genes statistically meaningless. The original data for this figure were deposited in and Additional file 1: Table S5