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UC San Diego biologists discover a motor protein that rewinds DNA

Two biologists at the University of California, San Diego have discovered the first of a new class of cellular motor proteins that "rewind" sections of the double-stranded DNA molecule that become unwound, like the tangled ribbons from a cassette tape, in "bubbles" that prevent critical genes from being expressed.

"When your DNA gets stuck in the unwound position, your cells are in big trouble, and in humans, that ultimately leads to death" said Jim Kadonaga, a professor of biology at UCSD who headed the study. "What we discovered is the enzyme that fixes this problem."

Conclusive proof that polar warming is being caused by humans

New research by the University of East Anglia (UEA) has demonstrated for the first time that human activity is responsible for significant warming in both polar regions.

The findings by a team of scientists led by UEA's Climatic Research Unit will be published online by the Nature Geoscience this week.

Virginia Tech engineers identify conditions that initiate erosion

Blacksburg, Va. -- Wind, water, and waves erode billions of tons of soil from the earth's surface. As a result, many rivers are plagued with excessive amounts of suspended sediment. According to the U.S. Environmental Protection Agency, such eroded sediment is the largest nonpoint source pollution in the environment.

Ultrafast lasers give CU-Boulder researchers a snapshot of electrons in action

In the quest to slow down and ultimately understand chemistry at the level of atoms and electrons, University of Colorado at Boulder and Canadian scientists have found a new way to peer into a molecule that allows them to see how its electrons rearrange as the molecule changes shape.

Transplantation: 'molecular miscegenation' blurs the boundary between self and non-self

A new discovery by London biologists may yield new ways of handling the problem of transplant rejection. In a research article published in the November 2008 print issue of The FASEB Journal (http://www.fasebj.org), the scientists confirm the two-way transfer of a molecule (called "MHC") that instructs the immune system to tell "self" from "non-self." By disrupting the transfer of this molecule, newly transplanted organs should become "invisible" to the host's immune system.

Optimal dose of vitamin E maximizes benefits, minimizes risk

Corvallis, Oregon – October 29, 2008 -- Vitamin E has been heralded for its ability to reduce the risk of blood clots, heart attack, and sudden death. Yet in some people, vitamin E causes bleeding. Scientists have known for more than 50 years that excess vitamin E promotes bleeding by interfering with vitamin K, which is essential in blood clotting. However, they haven't been able to pinpoint how the two vitamins interact.

UC Davis researchers discover a key to aggressive breast cancer

(SACRAMENTO, Calif.) — In trying to find out why HER2-positive breast cancer can be more aggressive than other forms of the disease, UC Davis Cancer Center researchers have surprisingly discovered that HER2 itself is the culprit. By shutting down its own regulator gene, HER2 creates a permissive environment for tumor growth.

Building on recent research showing that the regulator — labeled LRIG1 and commonly called "Lig-1" — limits the growth-promoting signals of HER2, the research team set out to clarify the role of Lig-1 in breast cancer.

Complete mitochondrial genome of 5,000-year-old mummy yields surprise

Researchers have revealed the complete mitochondrial genome of one of the world's most celebrated mummies, known as the Tyrolean Iceman or Ötzi. The sequence represents the oldest complete DNA sequence of modern humans' mitochondria, according to the report published online on October 30th in Current Biology, a Cell Press publication.

Mitochondria are subcellular organelles that generate all of the body's energy and house their own DNA, which is passed down from mother to child each generation. Mitochondrial DNA thus offers a window into our evolutionary past.

Following the Phoenicians: Genetic methodology complements historical record

A new study uses a sophisticated genetic strategy to reveal new roads past an apparent dead end in the historical record of a distinctive civilization that dominated the Mediterranean Sea during the first millennium BC. The research from National Geographic and IBM's Genographic Project, published by Cell Press in the November 14th issue of the American Journal of Human Genetics, describes a methodology that may prove to be useful for discovering previously undetected signals left by migrations for any historically documented expansion.

Ancient mummy has no modern children

The 5,300 year old human mummy – dubbed Öetzi or 'the Tyrolean Iceman' – is highly unlikely to have modern day relatives, according to new research published today.

A team comprising scientists from Italy and the UK has sequenced Öetzi's entire mitochondrial DNA (mtDNA) genome - which is passed down through the maternal line – and found that he belonged to a genetic lineage that is either extremely rare, or that has died out.

Tiny fungi may have sex while infecting humans

DURHAM, N.C.— A fungus called microsporidia that causes chronic diarrhea in AIDS patients, organ transplant recipients and travelers has been identified as a member of the family of fungi that have been discovered to reproduce sexually. A team at Duke University Medical Center has proven that microsporidia are true fungi and that this species most likely undergoes a form of sexual reproduction during infection of humans and other host animals.

Gene scan of Alzheimer's families identifies four new suspect genes

The first family-based genome-wide association study in Alzheimer's disease has identified the sites of four novel genes that may significantly influence risk for the most common late-onset form of the devastating neurological disorder. In their report in the November 7 American Journal of Human Genetics, being released online today, a team led by researchers from the MassGeneral Institute for Neurodegenerative Disease (MGH-MIND) describes how newly available technology is improving understanding of genetic mechanisms underlying the disease.

Researchers identify mechanism, possible drug treatment for tumors in neurofibromatosis

Researchers studying neurofibromatosis type 1 – a rare disease in which tumors grow within nerves – have found that the tumors are triggered by crosstalk between cells in the nerves and cells in the blood. The researchers, who were funded by the National Institutes of Health (NIH) and the Department of Defense (DOD), also found that a drug on the market for treating certain kinds of blood cancer curbs tumor growth in a mouse model of neurofibromatosis type 1. A clinical trial of the drug is underway in people with the disease.

Gleevec holds potential as first drug to successfully treat neurofibromatosis, IU scientists report

INDIANAPOLIS — Researchers at the Indiana University School of Medicine report that the anti-cancer drug Gleevec holds out promise to become the first effective treatment for neurofibromatosis, a genetic disease that has resisted treatments until now.

The research team is conducting clinical tests of the drug following successful laboratory tests and a "compassionate use" of the drug that showed dramatic results in a three-year-old girl at Riley Hospital for Children in Indianapolis.

Genographic scientists uncover new piece of Phoenician legacy

WASHINGTON (October 30, 2008)—The Phoenicians gave the world the alphabet and a love of the color purple, and a research study published today by Genographic scientists in the American Journal of Human Genetics (AJHG-D-08-00725R2) shows that they left some people their genes as well. The study finds that as many as one in 17 men in the Mediterranean basin may have a Phoenician as a direct male-line ancestor.