NIH New Innovator Award
Cool Videos: Know When to Fold Them
Posted on by Dr. Francis Collins
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 they’ve learned is that, 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
DNA and the Roots of Hair Roots
Posted on by Dr. Francis Collins

Source: National Cancer Institute, NIH; Bill Branson, photographer.
It’s intriguing to find the roots of physical traits: skin color, height, and those weird tufts of hair on Uncle Mike’s ears. We’re all curious to know why we look the way we do. But new technologies are allowing us to discover the precise genetic roots of human traits that vary across the world. Variations in our DNA have helped us resist diseases and adapt to different climates and foods, enabling us to colonize just about every environment on the planet.
Recent studies have pinpointed variations responsible for lighter skin in Northern climates (such as SLC24A5 [1]) and the ability to tolerate milk sugar (lactose) in adulthood [2]. But a new NIH-funded study of a gene variant that arose in China adds a fascinating wrinkle—the use of a mouse model to help understand a potential human advantage [3]. (Regular readers will note that last week in this space I wrote about how mouse models could sometimes be misleading—this week the mouse is a champion!)