Double-stranded oligonucleotides

Abstract

Antisense sequences, including duplex RNAi compositions, which possess improved properties over those taught in the prior art are disclosed. The invention provides optimized antisense oligomer compositions and method for making and using the both in in vitro systems and therapeutically. The invention also provides methods of making and using the improved antisense oligomer compositions.

1 . A method for introducing a double-stranded ribonucleic acid molecule comprising a first strand and a second strand into a eukaryotic cell in vitro, the method comprising contacting the eukaryotic cell with the double-stranded ribonucleic nucleic acid molecule,
 wherein from one to six of the nucleotides of the first strand of the double-stranded ribonucleic acid molecule are chemically modified at the 2′ positions, wherein said modification is a 2′-O-methyl modification;   wherein from one to six of the nucleotides of the second strand of the double-stranded ribonucleic acid molecule are chemically modified at the 2′ positions, wherein said modification is a 2′-O-methyl modification;   wherein the double-stranded ribonucleic acid molecule is between 18 and 30 nucleosides in length;   wherein at least one of the first strand or the second strand contains a 5′-terminal phosphorus containing moiety; and   wherein the double-stranded nucleic acid molecule is introduced into the eukaryotic cell and participates in RNA interference mediated degradation of RNA which shares sequence complementarity with at least one strand of the double-stranded nucleic acid molecule.   
     
     
         2 . The method of  claim 1 , wherein the double-stranded ribonucleic acid molecule is between 20 and 30 nucleosides in length. 
     
     
         3 . The method of  claim 1 , wherein the double-stranded ribonucleic acid molecule is 25 nucleosides in length. 
     
     
         4 . The method of  claim 1 , wherein the double-stranded ribonucleic acid molecule contains an overhang of at least one nucleoside on at least one end. 
     
     
         5 . The method of  claim 4 , wherein the overhang is a 3′ end overhang. 
     
     
         6 . The method of  claim 4 , wherein the nucleosides of the 3′ end overhang are deoxy T-deoxy T. 
     
     
         7 .- 8 . (canceled) 
     
     
         9 . The method of  claim 1 , wherein the eukaryotic cell is contacted with the double-stranded ribonucleic acid molecule in the presence of a transfection agent. 
     
     
         10 . The method of  claim 9 , wherein the transfection reagent is a cationic lipid. 
     
     
         11 . The method of  claim 1 , wherein the double-stranded ribonucleic acid molecule is introduced into the eukaryotic cell by electroporation. 
     
     
         12 . The method of  claim 1 , wherein a strand of said double-stranded ribonucleic acid molecule is complementary to a sequence of an mRNA expressed in said eukaryotic cell. 
     
     
         13 . (canceled) 
     
     
         14 . A method for introducing a double-stranded ribonucleic acid molecule comprising a first strand and a second strand into a eukaryotic cell in vitro, the method comprising contacting the eukaryotic cell with the double-stranded ribonucleic acid molecule,
 wherein at least one of the nucleomonomers of the first strand or the second strand of the double-stranded ribonucleic acid molecule is chemically modified at the 2′ position, wherein said modification is a 2′-O-methyl modification;   wherein the first strand and the second strand each have a length of less than 25 nucleomonomers and have a duplex length of at least 10 to at least 24 nucleomonomers;   wherein at least one of the first strand or the second strand contains a 5′-terminal phosphorus containing moiety; and   wherein the double-stranded nucleic acid molecule is introduced into the eukaryotic cell and participates in RNA interference mediated degradation of RNA which shares sequence complementarity with at least one strand of the double-stranded nucleic acid molecule.   
     
     
         15 . The method of  claim 14 , wherein the double-stranded ribonucleic acid molecule contains an overhang of at least one nucleomonomer on at least one end. 
     
     
         16 . The method of  claim 15 , wherein the overhang is a 3′ end overhang. 
     
     
         17 . The method of  claim 16 , wherein the nucleomonomers of the 3′ end overhang are deoxy T-deoxy T.