As most of you probably know, the human genome—our genetic instruction book—contains about 3 billion base pairs of DNA. But here’s a less well-known fact: if you would take the DNA from the nucleus of just one human cell and stretch it end-to-end, it would measure about 6 1/2 feet. How can a molecule of that length be packed into a cell nucleus that measures less than .00024 of an inch? Well, this fun video, which accompanies exciting new findings published in the journal Cell, serves to answer that fundamental question.
I’m proud to say that NIH helped to support the highly creative team of researchers that, over the course of the past five years, have mapped with unprecedented detail and precision how the human genome folds inside the cell’s nucleus. Among the many things that they’ve learned is, in much the same way that origami artists can craft a vast array of paper creatures using two simple folds, the genome is able to work its biological magic with just a few basic folds—including the all-important 3D loop
In their landmark work, the team from Baylor College of Medicine and Rice University in Houston; Harvard University, Cambridge, MA; and the Broad Institute of MIT and Harvard, found that the human genome is folded into roughly 10,000 loops. That number has surprised many, given that previous studies had suggested there could be more than 1 million such loops. But keep in mind that these loops are not static. They are constantly forming, unfolding, and then forming again, enabling DNA to be configured into an almost limitless variety of shapes with the potential to carry out a mind-boggling range of functions.
The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.