DNA-based digital data storage: how nature holds the key to the data storage problem

Digital data production is growing exponentially, but current storage technologies are not keeping up with demand. Some researchers are advocating for DNA-based data storage as an alternative. DNA can hold 9Tb per mm3 after considering practical system overheads, resulting in a storage density 115,000 times higher than current archival storage methods can provide. Additionally, DNA-based storage requires little to no maintenance and fewer resources than present storage technology, and it is unlikely to ever become obsolete. The DNA storage pipeline of going from bits to DNA bases and vice versa consists of the following steps: writing (encoding and DNA synthesis), storage, retrieval and reading (DNA sequencing and decoding). DNA synthesis is currently the major bottleneck for commercialising the technology due to its high costs and time consumption. This article discusses the principles of DNA-based storage, the current commercial position of DNA-mediated archival storage and technological improvements necessary for further upscaling.

CRISPR/Cas-mediated DNA base-editing in gene therapy targeting β-hemoglobinopathies

CRISPR-Cas-mediated DNA base-editing is a step up from the famous CRISPR/Cas9 genome editing platform. Base-editing is capable of modifying haematopoietic stem and progenitor cells (HSPCs). This approach is paramount when silencing the genetic regulators such as BCL11A which affects the expression of β- and γ-globin genes in β-hemoglobinopathies – sickle cell disease and β-thalassemia. High performance rates of the base-editors instill hope in everyday use of these techniques in the clinical setting.

The visualisation of Quadruple-Helix DNA in Living Human Cells

The DNA molecule is often associated with its well-known double-stranded helical B conformation, first discovered using crystallographic evidence sought by English chemist and x-ray crystallographer Rosalind Franklin. While this is the most common structure, it can also be found in two other double helical conformations, the A and Z forms, and it has also been found to adopt a range of other structures such as cruciform and slipped structures, and triple helices.1 The diversity of known possible non-B conformations has increased  with the discovery of four-stranded ‘quadruple helix’ DNA molecules, also known as ‘G-quadruplexes’ or ‘G4s’, having been detected in guanine-rich regions of the genome. While this form of DNA has been previously theorized to exist and has been synthesized ‘in vitro’ by researchers, it was only found to exist in human cells in 2013. 2 It has been found to have an essential role in telomere function, replication, transcription, and translation. However, imaging the molecules remained a challenge and in January 2021, researchers identified a probe exhibiting fluorescence in the presence of G-quadruplexes which could be used in order to visualize quadruple-stranded DNA in live cells using fluorescent lifetime imaging microscopy (FLIM).