| abstract |
The present invention is directed to compositions and methods for selectively reducing the expression of a gene product from a desired target gene in a cell and for the treatment of diseases caused by gene expression. More particularly, the present invention is directed to compositions comprising double stranded RNA (“dsRNA”) and methods of preparing them that can reduce the expression of target genes in eukaryotic cells. The dsRNA has a first oligonucleotide sequence between 25 and about 30 nucleotides in length and a second oligonucleotide sequence that anneals to the first sequence under biological conditions. Furthermore, at least one region of the sequence of dsRNA having a sequence of 19 nucleotides in length is sufficiently complementary to the nucleotide sequence of RNA produced from the target gene, and induces degradation of the target RNA by the RNAi mechanism. [Selection figure] None |