UPI NewsTrack Health and Science News

Amphibians confirmed as bellwethers

SANTA BARBARA, Calif., Oct. 29 (UPI) -- U.S. biologists say they've verified the predictive powers of amphibians, whose moist permeable skins make them susceptible to slight environmental changes.

Scientists have long suspected amphibians are good bellwethers for impending alterations in biodiversity during rapid climate change. The new University of California-Santa Barbara global study of species turnover among amphibians and birds has confirmed that belief.

"Our study supports the role of amphibians as 'canaries in the coal mine,' " said Lauren Buckley, a postdoctoral fellow at the university's National Center for Ecological Analysis and Synthesis. "Amphibians are likely to be the first to respond to environmental changes and their responses can forecast how other species will respond."

Buckley and University of California-San Diego Associate Professor Walter Jetz, co-author of the study, found that if the environment changes rapidly as one travels from one location to another, the amphibian and bird communities also change rapidly. However, amphibians change more quickly than birds.

The scientists said that finding confirms amphibians are particularly sensitive to changes in the environment, and that sensitivity is particularly acute given their narrow distributions.

The study appears in the early online edition of the Proceedings of the National Academy of Science.

Scientists find new way to fight leukemia

SYRACUSE, N.Y., Oct. 29 (UPI) -- U.S. scientists say they might have discovered a new way to fight leukemia and other forms of cancer by reprogramming cancerous cells back into normal cells.

A team of Syracuse University researchers led by Assistant Professor Michael Cosgrove says it has discovered a way to disrupt the protein switch that is a critical component in the process to create white blood cells. That discovery, researchers said, could lead to a more effective way to treat some forms of leukemia and revolutionize the approach to treating other forms of cancer.

"We believe our discovery is just the tip of the iceberg," Cosgrove said. "Our hope is that from the knowledge we have gained in understanding how these proteins work in normal cells, we will be able to find new ways to treat all types of leukemia. We also think the discoveries will have broad implications in treating other types of cancer."

The findings were recently published online in the Journal of Biological Chemistry and will appear in a forthcoming print edition.

Amphibians disappear from Yellowstone

STANFORD, Calif., Oct. 29 (UPI) -- A U.S. study suggests global warming is causing a "catastrophic" decrease in the numbers of frogs and salamanders living in Yellowstone National Park.

Stanford University graduate student Sarah McMenamin has spent three summers in a remote area of the park searching for frogs and salamanders in ponds that had been surveyed 15 years ago. She and Associate Professor Elizabeth Hadly say they've determined the decrease in the numbers of the amphibious environmental bellwethers is being caused by global warming.

Hadly, a co-author of the research paper, said the amphibians need the park's ponds for their young to hatch, but higher temperatures and drought are causing the water to evaporate.

"Precipitous declines of purportedly unthreatened amphibians in the world's oldest nature reserve indicate that the ecological effects of global warming are even more profound and are happening more rapidly than previously anticipated," the researchers wrote.

"They're just blinking off. It's depressing," added Hadly.

The researchers said they studied 100 years of climate and water records but could find no cause for the drying ponds other than a persistent change in temperature and precipitation.

The research appears in the online edition of the Proceedings of the National Academy of Sciences.

Puberty disorder gene is identified

AUGUSTA, Ga., Oct. 29 (UPI) -- U.S. scientists say they've identified a gene responsible for a variety of problems including mental retardation that arise during puberty.

Medical College of Georgia researchers discovered that when a gene called CHD7 mutates, it can produce a set of maladies such as hearing loss, heart defects and cleft lip and palate.

The researchers also determined CHD7 accounts for about 6 percent of two puberty disorders: idiopathic hypogonadotropic hypogonadism, or IHH; and Kallmann syndrome that, among other things, causes infertility.

In a study of 101 people with IHH and Kallmann syndrome, Dr. Lawrence Layman and colleagues found seven mutations of CHD7 that weren't present in nearly 200 healthy individuals.

"This suggests that (there) were mutations causing the disorder and we also showed that most of these mutations impaired the gene's function," Layman said.

The study's findings are detailed in The American Journal of Human Genetics.