1. CRISPR-Cas9 interrogation of a putative fetal globin repressor in human erythroid cells
- Author
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Chung, Jennifer E, Magis, Wendy, Vu, Jonathan, Heo, Seok-Jin, Wartiovaara, Kirmo, Walters, Mark C, Kurita, Ryo, Nakamura, Yukio, Boffelli, Dario, Martin, David I. K, Corn, Jacob E, and DeWitt, Mark A
- Subjects
BRII recipient: DeWitt - Abstract
Sickle Cell Disease and ß-thalassemia, which are caused by defective or deficient adult ß-globin (HBB) respectively, are the most common serious genetic blood diseases in the world. Persistent expression of the fetal ß-like globin, also known as ?-globin, can ameliorate both disorders by serving in place of the adult ß-globin as a part of the fetal hemoglobin tetramer (HbF). Here we use CRISPR-Cas9 gene editing to explore a potential ?-globin silencer region upstream of the δ-globin gene identified by comparison of naturally-occurring deletion mutations associated with up-regulated ?-globin. We find that deletion of a 1.7 kb consensus element or select 350 bp sub-regions from bulk populations of cells increases levels of HbF. Screening of individual sgRNAs in one sub-region revealed three single guides that caused increases in ?-globin expression. Deletion of the 1.7 kb region in HUDEP-2 clonal sublines, and in colonies derived from CD34+ hematopoietic stem/progenitor cells (HSPCs), does not cause significant up-regulation of ?-globin. These data suggest that the 1.7 kb region is not an autonomous ?-globin silencer, and thus by itself is not a suitable therapeutic target for gene editing treatment of ß-hemoglobinopathies.
- Published
- 2019