In a Nature paper published online in advance this week, investigators at the Whitehead Institute in Cambridge, Mass., and elsewhere show that the histone demethylase lysine-specific demethylase 1, or LSD1 "is essential in decommissioning enhancers during the differentiation of mouse embryonic stem cells." The Whitehead-led team says LSD1 "occupies enhancers of active genes that are critical for control of the state of ESCs," but is not essential for embryonic stem cell identity maintenance. "ESCs lacking LSD1 activity fail to differentiate fully, and ESC-specific enhancers fail to undergo the histone demethylation events associated with differentiation," the authors write.
Nature's David Cyranoski this week profiles geneticist Yusuke Nakamura, who left Japan for the "University of Chicago in Illinois, frustrated by Japan's lack of support for genomics and doubtful that the country would ever take a global lead in medicine." Cyranoski says Nakamura "has been a major force in Japanese science. … He is one of the country's best-funded researchers and has led some of Japan's biggest science projects." But some say Japan will not be affected by Nakamura's departure. Molecular biologist Yuko Ito tells Nature that Nakamura is "not the only one that can do genomics," adding that the field "has gone far in many directions, been incorporated in so many other fields. It doesn't depend on one person."
Over in Nature Genetics, researchers at Princeton University and elsewhere discuss the effects of chromosome-scale selective sweeps on genomic diversity in Caenorhabditis elegans. Taking a high-throughput selective sequencing approach on a collection of 200 wild C. elegans strains, the team found that the nematode's "genome variation is dominated by a set of commonly shared haplotypes on four of its six chromosomes, each spanning many megabases." Further, the team reports on its population genetic modeling experiments, which showed that "this pattern was generated by chromosome-scale selective sweeps that have reduced variation worldwide; at least one of these sweeps probably occurred in the last few hundred years," it writes.