- incorporation of dUTP by a DNA polymerase during amplicon generation, and
- excision of those uracils in amplified products and amplicon destruction catalyzed by a UDG.
For LAMP, reactions should be run with a ~50% inclusion of dUTP mixed with dTTP (e.g. 1.4 mM dATP, dCTP, dGTP, 0.7 mM dTTP and dUTP) and either Bst 2.0 or Bst 3.0 DNA polymerase should be used for efficient incorporation of dU without significant inhibition of the reaction. For the subsequent destruction of contaminant products, Antarctic Thermolabile UDG is strongly recommended over the more thermostable E. coli UDG. Include 0.5 μL of Antarctic Thermolabile UDG per 25 μL LAMP reaction, and simply set up and run your LAMP reactions as normal. UDG activity during setup and heating to 65 °C will quickly and efficiently destroy any contaminating products. If more stringent decontamination is required, then 10 minutes at 25 °C can be added to the beginning of the workflow.
For simplicity, dUTP and UDG have been included in an updated formulation for colorimetric LAMP detection: WarmStart Colorimetric LAMP 2X Master Mix with UDG and Fluorescent LAMP Kit WarmStart Fluorescent LAMP/RT-LAMP Kit (with UDG).