19nt
 21nt


 Select all
 Moderate to low (30%-52%) GC Content
 At least 3 A/Us at positions 15-19 (sense)
 A at position 19 (sense)
 A at position 3 (sense)
 U at position 10 (sense)
 No G/C at position 19 (sense)
 No G at position 13 (sense)

Reference:
Po-Chang Chang, Wei-Jie Pan, Chi-Wei Chen,Yu-Ting Chen and Yen-Wei Chu
(2012) DEsi: an design engine of siRNA that integrates SVMs prediction and feature filters, Biocatalysis and Agricultural Biotechnology, doi: 10.1016/j.bcab.2012.01.005