ESS exhibit significantly higher and more consistent editing levels and higher expression levels compared to all other sites. (A) Distribution of editing levels for ESS (black) and all other sites (white) (*P <10-6, Fisher’s exact test). (B) Mean editing levels for ESS versus all other sites (*P <7 × 10-22, Student’s two-tailed t-test). (C) Mean standard deviation for ESS and control (*P <4.6 × 10-8, two-tailed Student’s t-test). (D, E) ESS exhibits higher expression levels, as demonstrated by box plot (D) and by mean expression levels (E) (*P <10-28, two-tailed Student’s t-test).