Meng Zhang

Messenger RNA (mRNA) technology has become popular in the last few years due to its use in COVID-19 vaccines. This technology has been so groundbreaking that it recently won the 2023 Nobel Prize in medicine “for discoveries concerning nucleoside base modifications that enabled the development of effective mRNA vaccines against COVID-19.” This isn’t new technology, however— modified mRNAs have been studied for decades and show significant potential for therapeutic applications. Compared to unmodified mRNAs, modified mRNAs are more stable and have more favorable immunogenic effects.

The human genome consists of roughly 20,000 genes. Most of those genes contain instructions for making proteins, which work to build, repair, and regulate everything in our bodies. The genes are separated into distinct domains, and between those domains are boundary regions of DNA, which help to separate genes and ensure there isn’t crosstalk resulting in expression (genes turned on) or silencing (genes turned off) between the genes. Unfortunately, disruptions within boundary regions can still occur, leading to gene misexpression and disease in humans.

Researchers used single-molecule imaging to compare the genome-editing tools CRISPR-Cas9 and TALEN. Their experiments revealed that TALEN is up to five times more efficient than CRISPR-Cas9 in parts of the genome, called heterochromatin, that are densely packed. Fragile X syndrome, sickle cell anemia, beta-thalassemia and other diseases are the result of genetic defects in the heterochromatin.