Compositions and methods for inhibiting expression of Huntingtin gene
The invention relates to a double-stranded ribonucleic acid (dsRNA) for inhibiting the expression of the Huntingtin gene (HD gene), comprising an antisense strand having a nucleotide sequence which is less than 25 nucleotides in length and which is substantially complementary to at least a part of the HD gene. The invention also relates to a pharmaceutical composition comprising the dsRNA together with a pharmaceutically acceptable carrier; methods for treating diseases caused by the expression of the HD gene, or a mutant form thereof, using the pharmaceutical composition; and methods for inhibiting the expression of the huntingtin gene in a cell.
1. A double stranded ribonucleic acid (dsRNA) comprising a sense strand and an antisense strand, wherein said dsRNA is between 15 and 30 base pairs in length and the antisense strand comprises a region of complementarity which is substantially complementary to
5′ GUCACAAAGAACCGUGCAG 3′
(SEQ ID NO: 890).
2. The dsRNA of claim 1 , wherein said dsRNA is between is 18-25 base pairs in length.
3. The dsRNA of claim 1 , wherein said region of complementarity is complementary to at least 15 contiguous nucleotides of SEQ ID NO: 890.
4. The dsRNA of claim 1 , wherein said region of complementarity contains no more than 3 mismatches with SEQ ID NO:890.
5. The dsRNA of claim 1 , wherein said region of complementarity is fully complementary to SEQ ID NO:890.
6. The dsRNA of claim 5 , wherein said dsRNA is between 19 and 24 base pairs in length.
7. The dsRNA of claim 5 , wherein said antisense strand is between 19 and 21 nucleotides in length.
8. The dsRNA of claim 1 , wherein said dsRNA is blunt-ended.
9. The dsRNA of claim 1 , wherein said dsRNA comprises at least one single stranded nucleotide overhang.
10. The dsRNA of claim 1 , wherein said dsRNA comprises naturally occurring nucleotides.
11. The dsRNA of claim 1 , wherein said dsRNA comprises at least one modified nucleotide.
12. The dsRNA of claim 11 , wherein said modified nucleotide is chosen from the group of: a 2′-O-methyl modified nucleotide, a nucleotide comprising a 5′phosphorothioate group, and a terminal nucleotide linked to a cholesteryl derivative or dodecanoic acid bisdecylamide group.
13. The dsRNA of claim 11 , wherein said modified nucleotide is chosen from the group of: a 2′-deoxy-2′-fluoro modified nucleotide, a 2′-deoxy-modified nucleotide, a locked nucleotide, an abasic nucleotide, 2′-amino-modified nucleotide, 2′-alkyl-modified nucleotide, morpholino nucleotide, a phosphoramidate, and a non-natural base comprising nucleotide.
14. The dsRNA of claim 1 , wherein said dsRNA comprises at least one 2′-O-methyl modified nucleotide and at least one nucleotide comprising a 5′phosphorothioate group.
15. A pharmaceutical composition for inhibiting the expression of the Huntingtin (HD) gene in an organism, comprising the dsRNA of claim 1 and a pharmaceutically acceptable carrier.
16. The dsRNA of claim 1 , wherein said dsRNA comprises a cholesterol moiety.
17. A method for inhibiting expression of Huntingtin (HD) gene in a cell, the method comprising: (a) introducing into the cell a double-stranded ribonucleic acid (dsRNA) of claim 1 ; and (b) maintaining the cell produced in step (a) for a time sufficient to obtain degradation of the mRNA transcript of the HD gene, thereby inhibiting expression of the HD gene in the cell.
18. A method of treating or managing Huntingtin disease comprising administering to a patient in need of such treatment or management a therapeutically effective amount of said dsRNA of claim 1 .
19. The method of claim 18 , wherein said dsRNA is administered to the brain of the patient.
20. The method of claim 18 , wherein said dsRNA is administered by intrastriatal infusion.
21. The method of claim 19 , wherein administering the dsRNA of claim 1 to the brain causes a decrease in Huntingtin (HD) gene mRNA in the striatum.
22. The method of claim 19 , wherein administering the dsRNA of claim 1 to the brain causes a decrease in Huntingtin (HD) gene mRNA in the cortex.
23. A vector for inhibiting the expression of Huntingtin (HD) gene in a cell, said vector comprising a regulatory sequence operably linked to a nucleotide sequence that encodes at least one strand of a dsRNA, wherein one of the strands of said dsRNA is substantially complementary to 5′ GUCACAAAGAACCGUGCAG 3′(SEQ ID NO: 890) and wherein said dsRNA is between 15 and 30 base pairs in length and wherein said dsRNA, upon contact with a cell expressing said Huntingtin (HD) gene, inhibits the expression of said Huntingtin (HD) gene by at least 20%.
24. A cell comprising the vector of claim 23 .