Genetic Alteration of MicroRNA Affecting Cancer Pathways

MicroRNAs (miRNAs) are small endogenous noncoding RNA molecules regulating gene expression at posttranscriptional level through sequence-specific pairing. miRNA genes variations may have important effects at different functional levels including the transcription of miRNAs, maturation, and targeting. Biological computational tools and online repositories allow to analyze the effect of single-nucleotide polymorphism on miRNA target binding site and more generally to investigate the result of mutations in miRNA genes. Consequently, genetic mutations affecting miRNA-target interactions have been associated to alterations pathways associated to several diseases as well as cancer. In this chapter, we describe the biological evidence of miRNA genetic alterations and cancer associations together with computational resources to collect and analyze mutation-disease associations.