The ultimate goal then is to figure out how many different kinds of genes can be turned on or off without altering the underlying DNA sequence.
A first step is to actually see specific chromosomes. Smith and her team amazingly achieved this using a new imaging technology called "soft x-ray tomography." Via fluorescence, it provides 3-D views of cellular components.
The technique enabled the researchers to look right at specific chromosomes. In this case, Smith said, they were "the inactive X chromosome of female cells."
"With new fluorescent probes, we can start identifying the position of specific genes in context - inside the tangled network of DNA within the intact nucleus," she explained.
9 Gadgets That Will Get (and Keep) You Going
Smith continued, "A cell's nucleus contains the genetic code, its DNA. But while the structure of the DNA was determined more than 50 years ago, and we're rapidly determining the position of specific genes on chromosomes, no one had visualized the DNA within an intact nucleus - an unfixed, hydrated whole cell."