*2.2.2. Thermodynamic property for efficient RISC loading*

In a siRNA duplex, antisense strand with relatively low energy in 5' end is favourable for its loading into RISC complex. So, there should be difference in binding energy between the 5' end of the sense and antisense strand.

### **2.3. Sequence characteristics**

Years of research for finding appropriate designing parameters identified some sequence parameters enriched within efficient siRNAs. These sequence characteristics often contribute to efficient RISC loading or siRNA sequence specificity or stability issues.

## *2.3.1. Position specific nucleotide composition*

Sequence analysis of effective siRNAs revealed many position specific nucleotide compositions for enhancing potency of the siRNA. Some of these preferences are listed below in table 1-
