Electronic characteristics of BRCA1 mutations in DNA.

The efficient and low-cost way for gene mutation detection and identification are conducive for the detection of disease. Here, we report the electronic characteristics of the gene of breast cancer 1 in four common mutation types: duplication, single nucleotide variant, deletion, and indel. The electronic characteristics are investigated by the combination of density functional theory and non-equilibrium Green's function formulation with decoherence. The magnitude of conductance of these DNA molecules and mutational changes are found to be detectable experimentally. In this study, we also find the significant mutation type dependent on the change of conductance. Hence these mutations are expected to be identifiable. We find deletion type mutation shows the largest change in relative conductance (~97%), whereas the indel mutation shows the smallest change in relative conductance (~27%). Therefore, this work presents a possibility of electronic detection and identification of mutations in DNA, which could be an efficient method as compared to the conventional methods.

Effect of cytosine hydroxymethylation on DNA charge transport.

DNA hydroxymethylation plays a very important role in some biological processes, such as DNA methylation process. In addition, its presence can also cause some diseases. In this paper, the electrical properties of cytosine hydroxymethylated (Chm) DNA sequences are studied. The density functional theory (DFT) and Landauer-Büttiker framework are used to study the decoherence conductance and transmission of the Chm strands in different configurations, which provides a theoretical basis for the detection of Chm. The results show that the conductance of the hydroxymethylated DNA strand is smaller than that of the native and methylated strands. The length dependence of the Chm strands is also studied. With the length increasing, the conductance becomes larger. This study shows that DNA methylation can be detected electrically.