Corrections
An article on Tuesday misspelled the name of an Undergraduate Association vice-presidential candidate. His name is Pall M. Kornmayer ’11, not Cornmayer. The same article incorrectly implied in one instance that Kornmayer is the running mate Ariel A. Torres ’12 running mate. Torres’s running mate is actually Jarrett R. Remsberg ’11. Kornmayer is the running mate of Ian P. Tracy ’11.
An article last Tuesday about how the human genome folds in 3-D made several conceptual errors regarding Lieberman-Aiden’s research on the fractal globule model. The article incorrectly stated that the evidence suggesting a fractal globule implies that “the genome separates into two clear compartments: one where stretches of DNA are known to be active, and another where DNA is inactive and stowed away for future use.” Instead, this compartmentalization of the genome is an observation that was made by the Hi-C team at a larger scale, and is unrelated to the presence of a fractal globule at the smaller scale.
The article stated that “when unstretched onto its two-dimensional, double-helix form, the human genome spans nearly two meters in length,” which should read “when unstretched completely in one dimension.”
The paragraph stating that the fractal globule can be reduced further to a Peano curve is also inaccurate. The fractal globule is itself a polymer analogue of the Peano curve: The fractal globule signature is seen both in active and inactive regions of the genome, not only “in order to store less often-used genes and pack them more densely” as the article suggests.
The image credits for the fractal and equilibrium globule models were incorrect. These images should be credited to “Leonid Mirny and Maxim Imakaev” and not “Lenoid Mirny and Erez Lieberman-Aiden.” Mirny’s name was misspelled in these credits, appearing incorrectly as “Lenoid” instead of “Leonid.” The credit for the Peano curve graphic is correct.