Probability of a gene being expressed by length of gene – split by position of TSS with respect to A+/T+ boundary. The upper red line refers to genes whose TSS is within 5 k bases upstream of the A+/T+ boundary and 15 k bases downstream of this boundary and the lower blue line refers to genes whose TSS falls outside this range. The analysis is based on 2532 genes (red line) and 11291 genes (blue line). This figure explains why genes with TSS near this boundary are often expressed, despite the fact that these genes tend to be long genes (Figure 11a) and long genes tend to be less often expressed (Figure 12a). The plot shows plus and minus one standard error.
Evans BMC Genomics 2008 9:16 doi:10.1186/1471-2164-9-16