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Efficient CRISPR-Cas9-based genome editing of β-globin gene on erythroid cells from homozygous β⁰39-thalassemia patients.

ABSTRACT: Gene editing by the CRISPR-Cas9 nuclease system technology can be considered among the most promising strategies to correct hereditary mutations in a variety of monogenic diseases. In this paper, we present for the first time the correction, by CRISPR-Cas9 gene editing, of the β⁰39-thalassemia mutation, one of the most frequent in the Mediterranean area. The results obtained demonstrated the presence of normal β-globin genes after CRISPR-Cas9 correction of the β⁰39-thalassemia mutation performed on erythroid precursor cells from homozygous β⁰39-thalassemia patients. This was demonstrated by allele-specific PCR and sequencing. Accumulation of corrected β-globin mRNA and relevant "de novo" production of β-globin and adult hemoglobin (HbA) were found with high efficiency. The CRISPR-Cas9-forced HbA production levels were associated with a significant reduction of the excess of free α-globin chains. Genomic toxicity of the editing procedure (low indels and no off-targeting) was analyzed. The protocol might be the starting point for the development of an efficient editing of CD34⁺ cells derived from β⁰39 patients and for the design of combined treatments using, together with the CRISPR-Cas9 editing of the β-globin gene, other therapeutic approaches, such as, for instance, induction of HbA and/or fetal hemoglobin (HbF) using chemical inducers.

SUBMITTER: Cosenza LC

PROVIDER: S-EPMC8091488 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Hyperhaemolysis in a pregnant woman with a homozygous β0 -thalassemia mutation and two genetic modifiers.

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