In Science this week, a multi-institute team of Japanese researchers report new details on the role of epigenetics in sex determination, finding that histone demethylation influences whether an embryo will be male or female. Specifically, the protein Jmjd1a was discovered to control the demethylation of a sex-determining gene called Sry in mice. Loss of Jmjd1a function in developing animals resulted in the reversal of their sex from male to female.
Meanwhile, in Science Translational Medicine, a Harvard University team and collaborators describe a new method that could help detect brain tumors based on cellular levels of proteins and lipids. The in situ approach is based on Raman spectroscopy and judges the levels of proteins and lipids by sensing vibrations in chemical bonds. Tumors are high in protein and low in lipids, while normal tissue contains high levels of both, and the team was able to use their technique to accurately differentiate tumors from non-cancerous tissue in an infiltrative human glioblastoma xenograft mouse model.