Figure 2

Tissue-specific strong and weak poly(A) site usage. For each tissue, three bars represent the distance to the median usage according to three different cutoffs for the classification of strong and weak sites, for example, 60%, 75% and 90%. For each gene at a given cutoff, the poly(A) site with the percent of supporting ESTs above the cutoff was classified as a strong site. If there was a strong poly(A) site, other sites of the same gene were classified as weak sites. Only values for the weak sites are shown. Significant ones (p value < 0.05, Chi-squared test) are marked with asterisks.