Chinese Scientists Develop ContactSeek AI Framework for Precise DNA Base Editing Using AlphaFold3
Researchers from Peking University and East China Normal University have developed ContactSeek, an AI framework leveraging AlphaFold3's contact probability to enhance the precision of DNA base editors, reducing off-target effects while maintaining high on-target activity.
AI-Driven Precision in Gene Editing
A team of Chinese scientists has introduced a novel artificial intelligence framework called ContactSeek that harnesses AlphaFold3's contact probability predictions to dramatically improve the accuracy of DNA base editing. The research, led by Professor Yi Chengqi's group at Peking University's School of Life Sciences in collaboration with Professor Li Dali's team at East China Normal University, was published in Nature on July 22, 2026.
The Challenge of Off-Target Effects
Base editors are powerful tools for both fundamental research and therapeutic applications, capable of making single-nucleotide changes in genomic DNA. However, unintended edits at off-target sites have remained a critical bottleneck. The team addressed this by analyzing how base editor complexes interact with on-target versus off-target DNA sequences.
AlphaFold3's Untapped Signal
While AlphaFold3 – developed by Google DeepMind – is primarily known for predicting protein 3D structures, its latest version can also model interactions between proteins, nucleic acids, and multi-molecular complexes. The researchers discovered that the raw structural predictions sometimes failed to capture the conformational changes caused by single-base mismatches. However, the model's output of contact probability (CP) – a measure of how likely two residues are to be in close proximity – proved exquisitely sensitive to such mismatches.
“Contact probability can reflect local conformational changes induced by single base-pair mismatches and can also respond to interaction changes caused by single amino acid mutations,” the team noted in their study.
Building ContactSeek
ContactSeek integrates AlphaFold3-derived contact probabilities with high-throughput sequencing data on off-target editing events. The framework systematically identifies key amino acid residues in Cas proteins and deaminases that determine editing specificity, then guides the engineering of base editors with improved precision.
In benchmark tests, CP values clearly dropped in the mismatch region of off-target complexes compared to on-target ones – a signal that structural predictions alone missed. By mapping these differences, ContactSeek pinpointed novel Cas9 variants that significantly enhance the precision of adenine base editors (ABEs), suppressing DNA off-target editing while preserving robust on-target activity.
Implications for Future Gene Therapy
The work establishes a new paradigm for designing gene-editing tools with exceptional accuracy. By combining AI-based structural modeling with empirical editing data, ContactSeek enables rational engineering of editor components without exhaustive trial-and-error screening. The approach could accelerate the development of safer base editors for clinical applications.
Reference:
- Nature paper: Precise DNA base editing using AlphaFold3-based contact modelling
- Source: Peking University School of Life Sciences