Enables users to visualize the similarities and differences between several prediction algorithms. GTB is an online genome browser for visualizing the predicted tolerance of the human genome. It summarizes several in silico prediction algorithms and conservation scores: including 13 genome-wide prediction algorithms and conservation scores, 12 non-synonymous prediction algorithms and four cancer-specific algorithms. The GTB enables differences in prediction to be evaluated and facilitates rapid identification of potential regions of interest. The interactive browser can be used to facilitate the rapid identification of predicted intolerant regions across the genome and can also be used to visualize the concordance and subtle differences between multiple prediction algorithms.