Duplex-Repair enables highly accurate sequencing, despite DNA damage

Area of Science:

• Molecular Biology
• Genomics
• Biotechnology

Background:

• Accurate DNA sequencing is fundamental for biomedical research and diagnostics.
• Existing high-accuracy sequencing relies on detecting mutations on both DNA strands.
• Current DNA preparation methods may compromise this accuracy.

Purpose of the Study:

• To identify a critical flaw in current DNA preparation techniques for sequencing.
• To develop and validate a novel method to enhance DNA sequencing accuracy.
• To address the issue of false mutation detection in DNA sequencing.

Main Methods:

• Investigated DNA resynthesis during standard End Repair/dA-Tailing protocols.
• Quantified false mutation rates in cell-free DNA and tumor biopsies.
• Developed and tested the Duplex-Repair method for DNA preparation.
• Compared sequencing accuracy with and without Duplex-Repair.

Main Results:

• Standard DNA preparation can lead to 7-17% (cell-free DNA) and 32-57% (tumor biopsies) of interior duplex base pairs being resynthesized.
• This resynthesis can create false mutations, making them appear on both strands.
• Duplex-Repair reduced interior duplex base pair resynthesis by 8- to 464-fold.
• Duplex-Repair improved duplex sequencing accuracy by up to 8.9-fold.

Conclusions:

• A significant source of error in DNA sequencing arises from artifactual strand resynthesis during sample preparation.
• Duplex-Repair effectively mitigates this error, restoring high fidelity to duplex sequencing.
• This advancement is crucial for reliable genomic analysis in biomedicine.