Background A large effort to discover microRNAs (miRNAs) has been under way. Currently
miRBase is their primary repository, providing annotations of primary sequences, precursors
and probable genomic loci. In many cases miRNAs are identical or very similar between
related (or in some cases more distant) species. However, miRBase focuses on those
species for which miRNAs have been directly confirmed. Secondly, specific miRNAs or their
loci are sometimes not annotated even in well-covered species. We sought to address this …