Effective CRISPR/Cas9-mediated correction of a Fanconi anemia defect by error-prone end joining or templated repair

Area of Science:

• Molecular Biology
• Genetics
• Hematology

Background:

• Fanconi anemia (FA) is a genetic disorder causing bone marrow failure and cancer predisposition.
• FA patients have defective DNA repair mechanisms, complicating gene editing therapies.
• Hematopoietic stem cell gene editing is a potential therapeutic avenue for FA.

Purpose of the Study:

• To investigate the feasibility of CRISPR/Cas9 gene editing for correcting mutations in Fanconi anemia.
• To assess the efficacy of gene editing in restoring Fancf function and improving cellular survival.
• To evaluate the potential of gene editing strategies for treating bone marrow failure in FA.

Main Methods:

• CRISPR/Cas9 gene editing was used to correct a mutation in the Fancf gene.
• Error-prone end joining and templated gene correction strategies were employed.
• Cas9 nickase activity was utilized to achieve mono-allelic editing and minimize off-target mutations.

Main Results:

• CRISPR/Cas9 corrected Fancf function, increasing survival by 27% in the presence of mitomycin C.
• Templated gene correction, though inefficient (≤6%), conferred a proliferative advantage to corrected FA cells.
• Cas9 nickase activity enabled mono-allelic editing, successfully avoiding undesired mutagenesis.

Conclusions:

• DNA repair defects in Fanconi anemia do not prevent CRISPR/Cas9-mediated gene correction.
• Gene editing holds significant promise for developing pre-clinical models and therapeutic strategies for FA.
• This study provides a foundation for advancing gene editing approaches to combat bone marrow failure in FA.