COMPOSITIONS AND METHODS FOR TREATING HEMOGLOBINOPATHIES
The present invention features compositions and methods for editing deleterious mutations associated with hemoglobinopathies, such as sickle cell disease (SCD). In particular embodiments, the invention provides methods for correcting mutations in a beta globin polynucleotide using modified adenosine base editors termed “ABE8” having unprecedented levels (e.g., >60-70%) of efficiency.
1 . (canceled)
2 . A cell comprising:
i) a β-globin (HBB) polynucleotide comprising a single nucleotide polymorphism (SNP) associated with sickle cell disease or beta thalassemia; and
ii) a nucleobase alteration in a hemoglobin subunit gamma 1 and/or 2 (HBG1/2) promoter, wherein the nucleobase alteration effects an increase in gamma globin expression in the cell compared to a reference cell.
3 . The cell of claim 2 , wherein the nucleobase alteration in the HBG1/2 promoter disrupts repressor binding to the HBG1/2 promoter.
4 . The cell of claim 2 , wherein the nucleobase alteration is at position −114 of the HBG1/2 promoter.
5 . The cell of claim 2 , wherein the nucleobase alteration is an A to G alteration at position 5 or position 8 of the nucleotide sequence of SEQ ID NO: 177.
6 . The cell of claim 2 , wherein the SNP associated with sickle cell disease results in expression of an HBB polypeptide comprising a valine at amino acid position 7 referenced to SEQ ID NO: 26.
7 . The cell of claim 2 , wherein the cell is a red blood cell, or progenitor thereof.
8 . The cell of claim 2 , wherein the cell is a hematopoietic stem cell, a common myeloid progenitor, proerythroblast, erythroblast, reticulocyte, an erythrocyte, or a progenitor of one of the aforementioned cells.
9 . The cell of claim 8 , wherein the cell is a hematopoietic stem cell (HSC).
10 . The cell of claim 9 , wherein the HSC is CD34+.
11 . The cell of claim 2 , wherein the cell is in vivo or ex vivo.
12 . The cell of claim 2 , wherein the cell is a human cell.
13 . A pharmaceutical composition comprising the cell of claim 2 and a pharmaceutically acceptable carrier, vehicle, or excipient.
14 . A method for treating a hemoglobinopathy in a subject in need thereof, the method comprising administering to the subject the cell of claim 2 .
15 . The method of claim 14 , wherein the cell is autologous to the subject.
16 . The method of claim 14 , wherein the cell is allogenic to said subject.
17 . The method of claim 14 , wherein the hemoglobinopathy is sickle cell disease or beta thalassemia.
18 . The method of claim 14 , wherein the nucleobase alteration in the HBG1/2 promoter disrupts repressor binding to the HBG1/2 promoter.
19 . The method of claim 18 , wherein the nucleobase alteration is an A to G alteration at position 5 or position 8 of the nucleotide sequence of SEQ ID NO: 177.
20 . The method of claim 19 , wherein the SNP associated with sickle cell disease results in expression of an HBB polypeptide comprising a valine at amino acid position 7 referenced to SEQ ID NO: 26.
21 . The method of claim 20 , wherein the cell is a CD34+ hematopoietic stem cell.