MicroRNAs (miRNAs) are studied as key regulators of gene expression involved in different diseases. Several single nucleotide polymorphisms (SNPs) in miRNA genes or target sites (miRNA-related SNPs) have been proved to be associated with human diseases by affecting the miRNA-mediated regulatory function. To systematically analyze miRNA-related SNPs and their effects, we performed a genome-wide scan for SNPs in human pre-miRNAs, miRNA flanking regions, target sites, and designed a pipeline to predict the effects of them on miRNA-target interaction. As a result, we identified 48 SNPs in human miRNA seed regions and thousands of SNPs in 3' untranslated regions with the potential to either disturb or create miRNA-target interactions. Furthermore, we experimentally confirmed seven loss-of-function SNPs and one gain-of-function SNP by luciferase assay. This is the first case of experimental validation of an SNP in an miRNA creating a novel miRNA target binding. All useful data were complied into miRNASNP, a user-friendly free online database (http://www.bioguo.org/miRNASNP/). These data will be a useful resource for studying miRNA function, identifying disease-associated miRNAs, and further personalized medicine.
© 2011 Wiley Periodicals, Inc.