Fig. 12From: Selective forces and mutational biases drive stop codon usage in the human genome: a comparison with sense codon usageRatio between A + U occurrence at +1 site and region I in gene categories with increasing breadth of transcription. Transcriptome data were obtained from the Gene Expression Barcode (Barcode) database. Genes were clustered into four categories by proportion of cell types in which a gene was estimated as expressed (Pr). Values represent mean ± SEMBack to article page