Harvard Stem Cell Institute (HSCI) scientists collaborating with researchers at the University of Pennsylvania have developed a "genome-editing" approach for permanently reducing cholesterol levels in mice through a single injection, a development that could reduce the risk of heart attacks in humans by 40 to 90 percent.

"For the first iteration of an experiment, this was pretty remarkable," said Kiran Musunuru of HSCI, an assistant professor in Harvard's Department of Stem Cell and Regenerative Biology (SCRB), and a cardiologist at Harvard-affiliated Brigham and Women's Hospital. Musunuru stressed, however, that it could take a decade of concerted effort to get this new approach for fighting heart disease from the laboratory to phase I clinical trials in humans.

Scientists have announced results from a large-scale study that uses saliva as a tool for identifying children who are at risk for developing Type 2 diabetes. This team of investigators found significantly altered levels of salivary biomarkers in obese children. By testing this non-invasive approach to the study of metabolic diseases, the researchers hope to develop simplified screening procedures to identify people at risk of developing Type 2 diabetes. This work provides the first step in the development of early diagnosis and prevention strategies.

Cutaneous nevi, commonly known as moles, may be a novel predictor of breast cancer, according to two studies published in this week's PLOS Medicine. Jiali Han and colleagues from Indiana University and Harvard University, United States, and Marina Kvaskoff and colleagues from INSERM, France, report that women with a greater number of nevi are more likely to develop breast cancer.

The researchers reached these conclusions by using data from two large prospective cohorts– the Nurses' Health Study in the United States, including 74,523 female nurses followed for 24 years, and the E3N Teachers' Study Cohort in France, including 89,902 women followed for 18 years.

For the last 2.5 million years, our planet has experienced lengthy cold cycles with brief interruptions by warm ones. During cold periods, continental-scale ice sheets blanketed large tracts of the northern hemisphere and as the climate warmed up, these colossal glaciers receded, leaving Yosemite-like valleys and other majestic geologic features behind.

Obviously, the advance and retreat of the ice sheets also had a profound influence on the evolution and geographic distribution of many animals, including those that live today in the Arctic regions.

Why do so many criminals convicted of misdemeanors then get involved in violent crime?

It turns out that in many cases it's because they weren't misdemeanors at all, they were felony crimes that were reduced during plea bargaining. And that policy, according to an article in the American Journal of Preventive Medicine, leads to more violent crimes that could be prevented.

The small, preliminary study re-analyzed data on 787 individuals under age 35 who had violent misdemeanor convictions and purchased handguns in California in 1989 or 1990. The goal was to assess the impact of reduced criminal charges on gun purchases and subsequent crime. 

Combat is correlated in some to depression and substance abuse - post-traumatic stress disorder is part of the lexicon today, real and claimed by clerks who never heard a gunshot while in the military and then a general malaise for people who had any kind of stress.

But soldiers who endure the highest stress - those who kill in the heat of combat - are least likely to self-medicate, according to analysis of data by researchers with the Walter Reed Army Institute of Research and American University.

In "Changes in Alcohol Use after Traumatic Experiences: The Impact of Combat on Army National Guardsmen" in the journal Drug and Alcohol Dependence, they contradict common sociological wisdom.