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The effects of polymorphisms on human gene targeting
David R Deyle1, Li B Li, Gaoying Ren
1Department of Medicine, University of Washington, Seattle, WA, 98195, USA and Department of Biochemistry, University of Washington, Seattle, WA, 98195, USA.
Nucleic Acids Research
|December 28, 2013
Summary
DNA mismatches between gene editing tools and target DNA significantly reduce gene targeting in human cells. Even a single base pair mismatch lowers efficiency, but polymorphisms can be leveraged for allele-specific targeting.
Area of Science:
- Molecular Biology
- Genetics
- Gene Editing Technologies
Background:
- DNA mismatches between vector homology arms and chromosomal targets are known to reduce gene targeting efficiency in various species.
- This phenomenon, however, had not been previously documented in human cells.
Purpose of the Study:
- To investigate the impact of DNA mismatches on gene targeting frequencies in human cells.
- To explore the utility of homology arm polymorphisms for allele-specific targeting and optimizing vector design.
Main Methods:
- Utilizing gene editing techniques in human cell lines to assess the effects of varying degrees of homology between vector and target DNA.
- Introducing single nucleotide polymorphisms (SNPs) into homology arms to evaluate their influence on gene targeting outcomes.
Main Results:
- A single mismatched base pair between vector homology arms and the chromosomal target sequence was found to significantly decrease human gene targeting frequencies.
- Homology arm polymorphisms demonstrated the potential to direct allele-specific gene targeting.
- These polymorphisms could also be used to improve vector designs that are otherwise unfavorable due to deletions.
Conclusions:
- DNA sequence complementarity is critical for efficient gene targeting in human cells, with even minor mismatches causing substantial reductions.
- Homology arm polymorphisms offer a valuable tool for precise genetic engineering, enabling allele-specific modifications and enhancing the design of gene editing vectors.
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