Distribution of Mtb genes according to functional categories. The categories are adapted from Cole and his coworkers . For practical reasons, the categories of "Conserved hypothetical proteins" and "Proteins of unknown function" were joined (category (III) in the Figure). Category (VI) encompasses the functional classes which were either less abundant or non existent in the list of 189 antigens selected herein. The percentage of genes in each of the functional categories is provided, as retrieved from Camus and his coworkers for the whole genome (A) , and calculated for this study 189 selected antigens (B) and 45 top-ranking antigens (C).