**3. Functional categorization of** *Entamoeba histolytica* **DNA repair genes**

To define the putative functions of *E. histolytica* DNA repair genes in unrelated DNA repair processes, we investigated the functional diversity of genomic maintenance pathways using Gene Ontology (GO) annotations. Functional related gene groups were predicted by the David bioinformatic resources (http://david.abcc.ncifcrf.gov/gene2gene.jsp), using a functional classification tool which generates a gene-to-gene similarity matrix based in shared functional annotation using over 75,000 terms from 14 functional annotation sources, allowing the classification of highly related genes in functionally related groups. Results from this analysis revealed that a large number of DNA repair genes were miss-annotated in parasites genome databases (43%). However, our analysis clearly showed that the majority of these genes seems to participate in DNA repair related processes. Besides, 57% of genes were predicted to function in DNA repair related process. 11% of genes participates in DNA damage repair, and 18% and 8% have helicase and endonuclease functions, respectively (**Fig. 2**).

Fig. 2. **Functional categorizations of** *E. histolytica* **DNA repair genes.** Biological processes and molecular functions were determined using David software

(http://david.abcc.ncifcrf.gov/gene2gene.jsp). Percentage of genes included in individual categories is given.
