FAQ: Should I denature the siRNA Marker before loading on my native gel?

No. The siRNA marker is a mixture of three synthetic non-phosphorylated double-stranded RNA molecules, which is used for accurately measuring the size of double stranded siRNA and other small dsRNA molecules on native gels. The RNA duplexes of the marker share some sequence similarities, therefore, denaturation/reannealing will result in different sized species.