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Updated: Oct 19, 2025

Efficient Generation of hiPSC Neural Lineage Specific Knockin Reporters Using the CRISPR/Cas9 and Cas9 Double Nickase System
Published on: May 28, 2015
Making the cut with PAMless CRISPR-Cas enzymes.
Kathleen A Christie1, Benjamin P Kleinstiver1
1Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, 02114, USA; Department of Pathology, Massachusetts General Hospital, Boston, MA, 02114, USA; Department of Pathology, Harvard Medical School, Boston, MA, 02115, USA.
New CRISPR-Cas variants expand genome editing capabilities beyond natural enzyme limitations. These advancements allow scientists to precisely modify almost the entire genome, opening new avenues in genetic research.
Area of Science:
- Genetics
- Molecular Biology
- Biotechnology
Background:
- CRISPR-Cas systems are powerful tools for genome editing.
- Naturally occurring CRISPR-Cas enzymes have limitations in targeting specific genomic regions.
- A significant portion of the genome remains inaccessible to existing editing technologies.
Purpose of the Study:
- To overcome the limitations of natural CRISPR-Cas enzymes in genome editing.
- To develop novel Cas variants with expanded targeting capabilities.
- To enable precise genetic modification across a larger fraction of the genome.
Main Methods:
- Development and characterization of new CRISPR-Cas variants.
- In vitro and in vivo testing of variant editing efficiency and specificity.
- Comparative analysis of novel variants against wild-type Cas enzymes.
Main Results:
- Engineered Cas variants demonstrate significantly broader genome targeting range.
- These new variants overcome the accessibility limitations of natural CRISPR-Cas enzymes.
- Successful editing of previously inaccessible genomic loci was achieved.
Conclusions:
- Novel CRISPR-Cas variants represent a major advancement in genome editing technology.
- These variants unlock nearly the entire genome for precise genetic manipulation.
- The expanded editing capacity promises to accelerate genetic research and therapeutic development.
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