Question: Will adding a DNA repair step to repair nicks in genomic DNA improve my results?
Answer: We have tested adding a DNA repair step prior to running genomic DNA samples through the 10x Genome solution and have not observed a noticeable or consistent improvement in library complexity or average molecule length as reported by Long Ranger. At this point we would not recommend adding a DNA repair step. To ensure high quality HMW DNA samples, the following best practices are recommended:
- Avoid and/or reduce heat steps in gDNA extraction protocols, particularly during the final steps of the protocol such as eluting from beads or resuspending a precipitated pellet
- Use nuclease-free buffers to store gDNA, eg. TE (do not use dH2O).
- Use gDNA preparations within 6 months (when stored at -20°C) or 2 weeks (when stored at 4°C) and stored at concentrations ideally >20 ng/ul.
- Incorporate chelating compounds such as EDTA throughout the extraction protocol.
- Always pipet slowly and with wide bore pipet tips whenever possible.
Products: Genome, Exome