Accurate genomic variant detection in single cells with primary template-directed amplification

Area of Science:

• Genomics
• Molecular Biology
• Biomedical Research

Background:

• Accurate whole genome amplification (WGA) is crucial for advanced biomedical research, including single-cell genotyping and studying intratissue genetic diversity.
• Existing WGA methods face limitations in uniformity and accuracy, hindering detailed cellular-level genetic analysis.

Purpose of the Study:

• To introduce primary template-directed amplification (PTA), a novel isothermal WGA method.
• To demonstrate PTA's capability for uniform and accurate single-cell genome capture.
• To showcase PTA's utility in enabling new research avenues like environmental mutagenicity assessment and CRISPR editing evaluation.

Main Methods:

• Development of primary template-directed amplification (PTA), an isothermal WGA technique.
• Application of PTA for capturing single-cell genomes with high uniformity and accuracy (>95% genome coverage).
• Utilizing PTA to develop Direct Measurement of Environmental Mutagenicity (DMEM) for base-pair resolution mutagen interaction mapping.
• Employing PTA for genome-wide off-target indel and structural variant detection in CRISPR-edited cells.

Main Results:

• PTA reproducibly captures >95% of single-cell genomes with enhanced uniformity and accuracy compared to existing methods.
• Significantly improved variant calling sensitivity and precision were achieved using PTA.
• PTA enabled the development of DMEM for mapping mutagen interactions in single living human cells.
• PTA facilitated accurate, genome-wide detection of off-target variants in single CRISPR-edited cells.

Conclusions:

• PTA represents a significant advancement in WGA technology, overcoming major limitations of current approaches.
• The improved precision and accuracy of PTA unlock new possibilities for studying genetic diversity and evolution at the cellular level.
• PTA is a feasible tool for single-cell evaluations in edited tissues and for detailed mutagenicity studies.