Figure 4

Distribution of similar C2H2 zinc-finger domains on chromosome 19. Each zinc-finger sequence was assigned to one of eight different clusters based on a hierarchical clustering analysis (see ‘Analysis of C2H2 motifs in Materials and Methods’). Each of these clusters is represented by a different color: orange, red, violet, green, yellow, gray, light blue and magenta. We used the sequence divergence between pairs of zinc-fingers as the similarity metric in this analysis. The density associated with each cluster was normalized such that the total mass is one, and it is represented with a particular color in the figure. We found that five clusters of zinc-fingers are highly localized on particular regions of chromosome 19 (orange, red, violet, green and yellow). This supports the hypothesis that local duplications generated by unequal crossover events have been responsible for the expansion of clusters of C2H2 zinc-fingers