The mir-6 microRNA precursor appears to be specific to Drosophila species. In Drosophila melanogaster there are three microRNA precursors called dme-mir-6-1, dme-mir-6-2, dme-mir-6-3 that all give rise to identical mature microRNA sequences. Animal miRNAs are transcribed as ~70 nucleotide precursors and subsequently processed by the Dicer enzyme to give a ~22 nucleotide product. In this case the mature sequence comes from the 3' arm of the precursor. The extents of the hairpin precursors are not generally known and are estimated based on hairpin prediction. The products are thought to have regulatory roles through complementarity to mRNA. The involvement of Dicer in miRNA processing suggests a relationship with the phenomenon of RNA interference. miRNAs are numbered based on the sequence of the mature RNA.