Researchers at the Massachusetts Institute of Technology and Harvard University have developed a technique allowing them to see the exact order of nucleotides within a cell and to understand how various cells differ from one another.
The method, called “DNA microscopy,” uses chemical reactions and synthetic DNA tags that adhere to other DNA and RNA molecules in the cell. The tags are then replicated hundreds of times within the cell, interacting with one another and forming unique DNA labels. Through this process, DNA microscopy effectively maps the location of every molecule by noting where the boundaries of the various tags overlap. This process enables researchers to capture information about the location and function of different parts of the cell.
“We’ve used DNA in a way that’s mathematically similar to photons in light microscopy,” said lead author Joshua Weinstein, PhD, a postdoctoral associate at the Broad Institute of MIT. “This allows us to visualize biology as cells see it and not as the human eye does.”
DNA microscopy also will reveal genetic information about cells that is not accessible with traditional microscopy tools, such as which immune receptor genes are turned on or off and whether cells are healthy or contain disease-causing mutations.
“[This] is an entirely new way of visualizing cells that captures both spatial and genetic information simultaneously from a single specimen,” Dr. Weinstein said.
Sources: The New York Times, June 20, 2019; Weinstein JA, Regev A, Zhang F, et al. DNA microscopy: optics-free spatio-genetic imaging by a stand-alone chemical reaction. Cell. 2019 June 20. [Epub ahead of print]