Inside STAT: Peering deep inside cells with a ‘DNA microscope’ 

EACH DOT REPRESENTS A CELL, WITH COLORS INDICATING WHAT DNA SEQUENCES THEY CONTAIN. (BROAD INSTITUTE OF MIT AND HARVARD)

Just look. A new “DNA microscope,” brainchild of Broad Institute postdoc Joshua Weinstein, combines the precision of electron microscopy with DNA sequencing to reveal DNA and RNA in a cell — and identify the exact nucleotides (the A’s, T’s, C’s, and G’s) of each molecule. Here’s how STAT’s Sharon Begley explains it: Customized sequences of DNA drop into cells to tag DNA and RNA molecules. The tags grab the genetic material and then make hundreds of copies of the molecules that collide and undergo chemical reactions, producing new paired nucleotide sequences. After a DNA sequencer decodes them, a computer algorithm reconstructs the molecules’ original locations in the cells along with its nucleotide sequence. Weinstein has used these mesmerizing images to track cancer cell lines. One day, they might guide immunotherapy.