(A) Comparison of the observed (2743, red arrow) and the number of polymorphic sites within ESE sequences (predicted as per Fairbrother et al. 2002; Zhang and Chasin 2004; Goren et al. 2006) expected by simulation within human intergenic multiexonic lncRNAs. The distribution of expected number of polymorphic sites within ESEs is based on 1000 randomizations of SNPs within multiexonic lncRNA exons accounting for base composition. (B) Comparison of the nucleotide substitution patterns with respect to ESE motifs within 20 nt of exon boundaries and 20 nt located at the center of lncRNA exons. (C) Comparison of the nucleotide substitution patterns with respect to ESE motifs identified within multiexonic and monoexonic lncRNAs.
