Interfering RNA molecules
The present invention is related to a ribonucleic acid comprising a double stranded structure whereby the double-stranded structure comprises a first strand and a second strand, whereby the first strand comprises a first stretch of contiguous nucleotides and whereby said first stretch is at least partially complementary to a target nucleic acid, and the second strand comprises a second stretch of contiguous nucleotides whereby said second stretch is at least partially identical to a target nucleic acid, and whereby the double stranded structure is blunt ended.
1. A double-stranded siRNA molecule against a target nucleic acid, wherein the double-stranded siRNA molecule comprises a first strand and a second strand,
wherein the first strand comprises a first stretch that is complementary to the target nucleic acid,
wherein the second strand comprises a second stretch that is the same length as the first stretch and is complementary to the first stretch,
wherein the first strand and the second strand form a double-stranded structure comprising the first stretch and the second stretch,
wherein the first stretch and the second stretch each comprises contiguous alternating 2′-O-alkyl ribonucleotides, wherein the 2′-O-alkyl ribonucleotides alternate with unmodified or differently modified ribonucleotides,
wherein the 2′-O-alkyl ribonucleotides of the first strand are shifted by one ribonucleotide relative to the 2′-O-alkyl ribonucleotides of the second strand, and
wherein each of the first stretch and the second stretch consists of at least 17 and fewer than 30 ribonucleotides.
2. The double-stranded siRNA molecule of claim 1 , wherein the double-stranded siRNA molecule is blunt ended on both ends.
3. The double-stranded siRNA molecule of claim 1 , wherein at least one end of the double-stranded siRNA molecule has an overhang.
4. The double-stranded siRNA molecule of claim 3 , wherein the overhang has one to eight nucleotides.
5. The double-stranded siRNA molecule of claim 3 , wherein the 3′ end of the first strand has an overhang.
6. The double-stranded siRNA molecule of claim 3 , wherein the 5′ end of the first strand has an overhang.
7. The double-stranded siRNA molecule of claim 3 , wherein the 3′ end of the second strand has an overhang.
8. The double-stranded siRNA molecule of claim 3 , wherein the 5′ end of the second strand has an overhang.
9. The double-stranded siRNA molecule of claim 1 , wherein each of the first strand and the second strand consists of at least 18 nucleotides.
10. The double-stranded siRNA molecule of claim 1 , wherein the 2′-O-alkyl ribonucleotides are 2′-O-methyl ribonucleotides.
11. The double-stranded siRNA molecule of claim 10 , wherein the 2′-O-methyl ribonucleotides alternate with the unmodified ribonucleotides.
12. The double-stranded siRNA molecule of claim 1 , wherein the differently modified ribonucleotides have an amino, fluoro, different alkoxy, or alkyl modification at the 2′-position.
13. The double-stranded siRNA molecule of claim 10 , wherein the 2′-O-methyl ribonucleotides alternate with 2′-fluoro ribonucleotides.
14. The double-stranded siRNA molecule of claim 1 , wherein the first stretch and the second stretch each comprises contiguous alternating single 2′-O-alkyl ribonucleotides, and wherein the single 2′-O-alkyl ribonucleotides alternate with the unmodified ribonucleotides.
15. The double-stranded siRNA molecule of claim 14 , wherein the single 2′-O-alkyl ribonucleotides are 2′-O-methyl ribonucleotides.
16. The double-stranded siRNA molecule of claim 1 , wherein the first stretch and the second stretch each comprises contiguous alternating single 2′-O-alkyl ribonucleotides, and wherein the single 2′-O-alkyl ribonucleotides alternate with the differently modified ribonucleotides.
17. The double-stranded siRNA molecule of claim 16 , wherein the single 2′-O-alkyl ribonucleotides are 2′-O-methyl ribonucleotides.
18. The double-stranded siRNA molecule of claim 16 , wherein the differently modified ribonucleotides have an amino, fluoro, different alkoxy, or alkyl modification at the 2′-position.
19. The double-stranded siRNA molecule of claim 16 , wherein the single 2′-O-alkyl ribonucleotides are 2′-O-methyl ribonucleotides, and the differently modified ribonucleotides are 2′-fluoro ribonucleotides.
20. The double-stranded siRNA molecule of claim 1 , wherein the 5′ ribonucleotide of the first stretch is a 2′-O-alkyl modified ribonucleotide.
21. The double-stranded siRNA molecule of claim 11 , wherein the 5′ ribonucleotide of the first stretch is a 2′-O-methyl ribonucleotide.
22. The double-stranded siRNA molecule of claim 13 , wherein the 5′ ribonucleotide of the first stretch is a 2′-O-methyl ribonucleotide.
23. The double-stranded siRNA molecule of claim 14 , wherein the 5′ ribonucleotide of the first stretch is a 2′-O-alkyl modified ribonucleotide that alternates with an unmodified ribonucleotide.
24. The double-stranded siRNA molecule of claim 16 , wherein the 5′ ribonucleotide of the first stretch is a 2′-O-alkyl modified ribonucleotide that alternates with a differently modified ribonucleotide.
25. The double-stranded siRNA molecule of claim 19 , wherein the double-stranded siRNA molecule is blunt on at least one end.
26. The double-stranded siRNA molecule of claim 19 , wherein at least one end of the double-stranded siRNA molecule has an overhang of one to eight nucleotides.
27. The double-stranded siRNA molecule of claim 26 , wherein the 3′ end of the first strand has an overhang.
28. The double-stranded siRNA molecule of claim 26 , wherein the 5′ end of the first strand has an overhang.
29. The double-stranded siRNA molecule of claim 26 , wherein the 3′ end of the second strand has an overhang.
30. The double-stranded siRNA molecule of claim 26 , wherein the 5′ end of the second strand has an overhang.