DNA nanostructures and miRNAs as biomarkers

Compared to its antibody-based counterparts, DNA based diagnostic device are more stable and do not require a cold-chain, the maintenance of proteins at a cool temperature to avoid degradation. DNA has emerged as a promising material that allows researchers to construct novel designs as its structure could be predicted easily and accurately. Examples of DNA nanostructures include nano-tweezers to detect norovirus and a DNA ‘Nano-Claw’ to detect membrane markers of cancer cells. DNA Boolean logic gates have been constructed to produce signals in the presence of multiple targets, such as OR-gate and AND-gate DNA tetrahedra that generate fluorescence resonance energy transfer (FRET) signal when multiple inputs hybridize with the probe. As for the targets to be detected, different microRNAs (miRNAs) have been identified to be associated with cancers. For example, miR-15b-5p, miR-338-5p, and miR-764 found in plasma are potential biomarkers for detecting hepatocellular carcinoma cancer (HCC), a common type of liver cancer. It has already been reported that it is promising to use these biomarkers - miRNAs to detect cancers. For Huntington’s disease, Hsa-miR-34b can be used as a biomarker. This miRNA is stable in the plasma, allowing the diagnosis to be carried out just by extracting small amounts of the patient’s blood. The miRNA is also elevated in pre-manifest Huntington’s Disease, which allows HD to be detected at the earliest stage possible, before the surfacing of symptoms.