Public release date: 26-Mar-2012 [ | E-mail | Share ] Contact: Peggy Calicchia calicchi@cshl.edu 516-422-4012 Cold Spring Harbor Laboratory March 27, 2012 Large numbers of people moved between Africa and Europe during recent and well-documented time periods such as the Roman Empire, the Arab conquest, and the slave trade, and genetic evidence of these migrations lives on in Europeans today. But were there more ancient migrations? In a study published online today in Genome Research, researchers present the first genetic evidence for prehistoric gene flow between Africa and Europe, dating back as far as 11,000 years ago. To trace the evolution and ancestry of humans, scientists study the DNA sequence of the mitochondria, a specialized cellular structure that produces energy for the cell and carries genetic information that is separate from the rest of the genome that resides in the nucleus. While the nuclear genome is a mix of genetic information from both mother and father, the mitochondrial DNA (mtDNA) is passed directly from mother to child without any contribution of DNA from the father. But not everyone's mtDNA is exactly alike: over long periods of time, small changes in the mtDNA sequence have arisen in different populations. Geneticists can … Continue reading →

- Human genome and mouse studies identify new precise genetic links Newswise Working with genetically engineered mice and the genomes of thousands of people with schizophrenia, researchers at Johns Hopkins say they now better understand how both nature and nurture can affect ones risks for schizophrenia and abnormal brain development in general. The researchers reported in the March 2 issue of Cell that defects in a schizophrenia-risk genes and environmental stress right after birth together can lead to abnormal brain development and raise the likelihood of developing schizophrenia by nearly one and half times. Our study suggests that if people have a single genetic risk factor alone or a traumatic environment in very early childhood alone, they may not develop mental disorders like schizophrenia, says Guo-li Ming, M.D., Ph.D., professor of neurology and member of the Institute for Cell Engineering at the Johns Hopkins University School of Medicine. But the findings also suggest that someone who carries the genetic risk factor and experiences certain kinds of stress early in life may be more likely to develop the disease. Pinpointing the cause or causes of schizophrenia has been notoriously difficult, owing to the likely interplay of multiple genes and environmental triggers, … Continue reading →

Public release date: 26-Mar-2012 [ | E-mail | Share ] Contact: Karen N. Peart karen.peart@yale.edu 203-432-1326 Yale University Obese youths with particular genetic variants may be more prone to fatty liver disease, a leading cause of chronic liver disease in children and adolescents in industrialized countries, according to new findings by Yale School of Medicine researchers. The study, which focused on three ethnic groups, is published in the March issue of the journal Hepatology. Led by Nicola Santoro, M.D., associate research scientist in the Department of Pediatrics at Yale School of Medicine, the authors measured the hepatic, or liver, fat content of children using magnetic resonance imaging. The study included 181 Caucasian, 139 African-American and 135 Hispanic children who were, on average, age 13. "We observed that a common genetic variant known as Patatin-like phospholipase domain containing protein-3 (PNPLA3) working with a regulatory protein called glucokinase (GCKR), was associated with increased triglycerides, very low-density lipoproteins levels, and fatty liver," said Santoro. Santoro explained that his observations could help unravel the genetic mechanisms that contribute to liver fat metabolism. "This may drive the decisions about future drug targets to treat hypertriglyceridemia and non-alcoholic fatty liver disease," he said. Childhood obesity is … Continue reading →

Houston researchers are reporting that adult stem cells have a modest benefit in younger patients with heart failure, the first large-scale evidence that the controversial yet promising new therapy can be developed to help millions of people with the disease. In a study presented at a cardiology conference Saturday, Texas Heart Institute doctors presented results of a clinical trial showing that cells derived from patients' own bone marrow produce a small but significant increase in the heart's ability to pump oxygen-rich blood. "This study moves us one step closer to being able to help patients with severe heart failure who lack other alternatives," said Dr. James Willerson, president of the Texas Heart Institute and the study's principal investigator. "It also points to a future in which stem cells regenerate the heart." The study did not find improvements in a number of heart function measures, but Willerson and other study leaders said it yielded key information about the specific adult stem cells with the greatest therapeutic potential. The trial used a number of stem cell types. Transplants limited About 6 million people in the United States have heart failure, a progressive and eventually fatal disease in which the heart loses the … Continue reading →

Public release date: 24-Mar-2012 [ | E-mail | Share ] Contact: Beth Casteel bcasteel@acc.org 240-328-4549 American College of Cardiology CHICAGO -- A new study found that using a patient's own bone marrow cells may help repair damaged areas of the heart caused by heart failure, according to research presented today at the American College of Cardiology's 61st Annual Scientific Session. The Scientific Session, the premier cardiovascular medical meeting, brings cardiovascular professionals together to further advances in the field. Millions of Americans suffer from heart failure, the weakening of the heart muscle and its inability to pump blood effectively throughout the body. If medications, surgery, or stents fail to control the disease, doctors often have few treatment options to offer. This is the largest study to date to look at stem cell therapy, using a patient's own stem cells, to repair damaged areas of the heart in patients with chronic ischemic heart disease and left ventricular dysfunction. Researchers found that left ventricular ejection fraction (the percentage of blood leaving the heart's main pumping chamber) increased by a small but significant amount (2.7 percent) in patients who received stem cell therapy. The study also revealed that the improvement in ejection fraction correlated … Continue reading →