Comparative Study of Canine and Human miRNAs and CpG Islands

MicroRNA (miRNA) has been recognized as a major factor in the regulation of gene expression in mammalian species and aberrant DNA methylation of tumor suppressor miRNAs due to CpG Island. Hypermethylation is emerging as another common mechanism of cancer. Because of experimental identification of miRNAs and their targets is difficult, comparative computational analysis is a popular method to identify new miRNAs and their associated targets. In this manuscript, we have performed a comparative analysis of the canine and human genome in order to find new miRNAs associated to CpG Islands. Human and canine miRNAs and genomes were obtained from mirBase and GenBank respective llythe genomes. A total of 67 miRNAs with nearby CGI were identified in the canine genome and 178 in the human genome, with one hundred and thirteen miRNAs showing some degree of homology between both species. This analysis also permitted the identification of uncatalogued miRNAs in the canine genome. The possible existence of these miRNAs is supported by the similarity score of 75% in miRbase. Our results support the notion that miRNA landscape in the canine genome is still to reveal itself in this species which develops cancers in higher rates than humans.