The white horse has been an icon for dignity, purity and good guys across various human cultures all over the world but only now has an international team been able to identify the mutation that causes this fascinating trait.

Their analysis shows that white horses carry an identical mutation that can be traced back to a common ancestor that lived thousands of years ago. The study is interesting for medical research since this mutation also enhance the risk for melanoma.

The great majority of white horses carry the dominant mutation 'Greying with age.' A Grey horse is born colored (black, brown or chestnut) but the greying process starts already during its first year and they are normally completely white by six to eight years of age, though the skin remains pigmented. Thus, the process resembles greying in humans but the process is ultrafast in these horses. The research presented now demonstrates that all Grey horses carry exactly the same mutation which must have been inherited from a common ancestor that lived thousands of years ago.

Logic says that just as air and water preceded life, so must the 'niche', the hospitable environment that shelters adult stem cells in tissue and provides factors necessary to keep them young and vital, must have emerged before its stem cell dependents.

A team of scientists at the Salk Institute for Biological Studies led by Leanne Jones, Ph.D., assistant professor in the Laboratory of Genetics, now suggests that this is not always the case. They report in the July 20 advance online edition of Nature that the cells that comprise a specialized niche in the testis of fruit flies actually emerge from adult stem cells, a finding with implications for regenerative medicine, aging research, and cancer therapeutics.

Long DNA sequences, or palindromes, change the shape of the molecule from double helix to hairpin-like formation, which causes replication to stall. Altered or stalled replication causes chromosomal breaking, resulting in cancers and diseases.

In the past 10 years, researchers in genome stability have observed that many kinds of cancers are associated with areas where human chromosomes break. More recently, scientists have discovered that slow or altered replication causes chromosomal breaking. But why does DNA replication stall?

In a Tufts University study published in the July 14 issue of Proceedings of the National Academy of Sciences of the United States of America, a team of biologists have found a relationship between peculiar DNA sequences named palindromes and replication delays.

For the first time, researchers have successfully grown functional human blood vessels in mice using cells from adult human donors — an important step in developing clinical strategies to grow tissue, researchers report in Circulation Research: Journal of the American Heart Association.

The researchers combined two different types of progenitor cells in a culture dish of nutrients and growth factors, then washed off the nutrients and implanted the cells into mice with weakened immune systems. Once implanted, the progenitor cell mixture grew and differentiated into a small ball of healthy blood vessels.

Progenitor cells are similar to stem cells but can only differentiate into specific cells, while stem cells can differentiate into practically any cell in the body.

Overweight mothers give birth to offspring who become even heavier, resulting in amplification of obesity across generations, said Baylor College of Medicine researchers in Houston who found that chemical changes in the ways genes are expressed – a phenomenon called epigenetics -- could affect successive generations of mice.

"There is an obesity epidemic in the United States and it's increasingly recognized as a worldwide phenomenon," said Dr. Robert A. Waterland, assistant professor of pediatrics – nutrition at BCM and lead author of the study that appears in the International Journal of Obesity. "Why is everyone getting heavier and heavier? One hypothesis is that maternal obesity before and during pregnancy affects the establishment of body weight regulatory mechanisms in her baby. Maternal obesity could promote obesity in the next generation."

The expectation that East-Asian people emphasize physical symptoms of depression (e.g. headaches, poor appetite or aches/pains in the body) is widely acknowledged, yet the few available empirical studies report mixed data on this issue. A new study from the Centre for Addiction and Mental Health (CAMH) debunks this cultural myth, and offers clinicians valuable insight to into cultural context when assessing a patient, leading to more accurate diagnosis.