non-coding RNA small interfering RNA Alan Ruttenberg Should requested and then imported from ChEBI WEB:https://en.wikipedia.org/w/index.php?title=Special:CiteThisPage&page=Small_interfering_RNA&id=685334024#Small_interfering_RNA siRNA small interfering RNA (siRNA) is a class of double-stranded RNA molecules, 20-25 base pairs in length. siRNA plays many roles, but it is most notable in the RNA interference (RNAi) pathway, where it interferes with thes expression of specific genes with complementary nucleotide sequences.