Quantum and classical effects in DNA point mutations: Watson-Crick tautomerism in AT and GC base pairs.

  title={Quantum and classical effects in DNA point mutations: Watson-Crick tautomerism in AT and GC base pairs.},
  author={Louie Slocombe and J. S. Al-Khalili and Marco Sacchi},
  journal={Physical chemistry chemical physics : PCCP},
Proton transfer along the hydrogen bonds of DNA can lead to the creation of short-lived, but biologically relevant point mutations that can further lead to gene mutation and, potentially, cancer. In this work, the energy landscape of the canonical A-T and G-C base pairs (standard, amino-keto) to tautomeric A*-T* and G*-C* (non-standard, imino-enol) Watson-Crick DNA base pairs is modelled with density functional theory and machine-learning nudge-elastic band methods. We calculate the energy… Expand
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