Signs of Depression

By Maggie Fox, Health and Science Editor

WASHINGTON (Reuters) - Researchers who figured out how to make valued embryonic stem cells out of ordinary skin cells said on Friday they had found a way to cut one cancer-causing ingredient out of the mix.

But it came at a price -- the method may be safer, but it is also less efficient.

Shinya Yamanaka of Kyoto University in Japan said the findings, published in the journal Nature Biotechnology, demonstrate that the stem cell breakthrough may have been exciting, but is nowhere near ready to be used in humans.

Earlier this month, teams led by Yamanaka and James Thomson of the University of Wisconsin in Madison each reported separately that they had used four genes to transform ordinary skin cells called fibroblasts into induced pluripotent stem cells -- iPS cells for short.

Their reports showed a way to get perfectly matched cells from patients that have at least some of the powers of embryonic stem cells, but without having to use cloning technology or embryos.

The hope is to find a way for new medical treatments that can make use of the body's own regenerative powers.

Yamanaka's team, working with a team at the Gladstone Institute of Cardiovascular Disease in San Francisco, used different genes than Thomson's team did.

One of the four genes in Yamanaka's restorative cocktail is called c-Myc1. They grew live mice from their new cells, but later found that the mice were prone to develop tumors.

So they left out c-Myc1. It worked, although not nearly as well. The new method was about half as efficient, they reported.

"Mice derived from Myc-negative iPS cells did not develop tumors during the study period," they wrote. "Future study is required to determine whether these mice develop tumors later in life," they added.

"Furthermore, we generated human iPS cells from adult dermal fibroblasts without MYC."

Both teams of researchers say they are still trying to fine-tune the precise genetic cocktail needed to turn back the clock on skin cells and make them act as if they came from a days-old human embryo -- one with just eight or so cells, each one of which has the power to give rise to all the tissues and cells found in the human body.

Yamanaka's team said it is possible that the other three genes they used -- called Oct3/4, Sox2 and Klf4 -- may somehow activate Myc that naturally is found in the DNA of the skin cells.

Politicians have welcomed the reports of reprogramming normal cells and said it shows there is no need to continue work on controversial stem cells taken from human embryos.

But most scientists in the field say it is important to continue to work with all kinds of stem cells, as scientists still do not understand quite how they work -- or how to use them in treating people.

(Editing by Will Dunham and Eric Walsh)

By Matt Spetalnick

MOUNT AIRY, Maryland (Reuters) - President George W. Bush on Friday announced a trip to Africa early next year for a first-hand look at U.S.-sponsored HIV/AIDS programs and pressed Congress to approve a doubling of funds to combat the disease globally.

Bush used an appearance at a church in Mount Airy, Maryland, the day before World AIDS Day to reaffirm his administration's multibillion-dollar commitment to fighting what he called the "scourge of HIV/AIDS."

"We rededicate ourselves to a great purpose. We will turn the tide against HIV/AIDS, once and for all," Bush said after meeting members of nongovernmental organizations and faith-based groups working in the hardest-hit countries.

AIDS activists have praised Bush's global anti-AIDS effort for getting life-extending drugs to people who otherwise would go without them, but have criticized its prevention measures for focusing too heavily on encouraging sexual abstinence.

Police arrested about 40 people staging a sit-in protest on the sidewalk in front of the White House against requirements in the U.S. program that at least a third of the funds be directed to promoting sexual abstinence until marriage.

Offering an upbeat assessment of his administration's anti-AIDS effort, Bush said he and first lady Laura Bush would visit sub-Saharan Africa early next year to see "the results of America's generosity."

He gave no dates or itinerary for the trip, his second to the region since taking office in 2001. He made a five-nation tour in 2003 during which he visited AIDS patients in Uganda.

Bush sees his initiatives against AIDS and malaria as foreign policy successes, and a trip to Africa in his final year in office could underscore that and give a boost to a legacy expected to be dominated by the unpopular war in Iraq.

Flanked by participants from Friday's meeting outside Washington, Bush urged Congress to authorize legislation doubling the U.S. financial commitment to combat AIDS globally to $30 billion over five years, starting next year.

The program is focused on 15 countries -- 12 in Africa, plus Vietnam, Haiti and Guyana.

In 2003 Bush launched a five-year, $15 billion initiative called the President's Emergency Plan for AIDS Relief, or PEPFAR, to provide drugs to treat people infected with the human immunodeficiency virus that causes AIDS and support prevention efforts.

"I call on Congress to show America's leadership and compassion by reauthorizing the emergency plan," he said.

More than 33 million people are infected with the AIDS virus, according to the latest U.N. estimate.

Bush said the U.S. plan had helped increase the number of people in sub-Saharan Africa receiving antiretroviral drugs to 1.4 million from 50,000 five years ago.

(Editing by Vicki Allen)

By Ben Hirschler

LONDON (Reuters) - Genetic tests to assess disease risk are proliferating but many are a waste of money and tell people little more than they would know from studying family history, medical experts said on Friday.

A host of companies now offer tests, typically costing hundreds of dollars, to calculate genetic risks for common conditions like cancer, diabetes and heart disease that involve multiple genes.

But Christine Patch, a genetic counselor at Guy's and St Thomas' NHS Foundation Trust and a member of Britain's Human Genetics Commission, said most had little clinical relevance.

"My message is you are wasting your money," she told a news briefing.

People also faced either unnecessary anxiety, if a test showed a raised risk, or false reassurance, if they were given an all-clear, she added.

Paul Pharoah, from the Cancer Research UK department of oncology at Cambridge University, said real strides were being made in science but researchers still did not know enough about enough genes for tests to be really useful.

Scientists have linked a growing number of genes to common diseases but these genes typically interact in a complicated fashion and their ultimate effect is influenced by environmental factors in ways that are poorly understood.

GENOME-WIDE SEARCH

The field of genetic testing has traditionally involved looking at a few specific genes.

But that is changing with the launch of new genome-wide searches that promise a brave new world of targeted healthcare, in which each individual can see his or her genetic code.

Two companies, Iceland's Decode Genetics Inc and 23andMe, a U.S. firm funded by Google Inc, launched rival services earlier this month offering people a glimpse of their entire genome for just under $1,000.

A third unlisted U.S. company, Navigenics, is set to join the fray shortly.

Stuart Hogarth of the Institute for Science and Society at University of Nottingham said the entry of these new players, with substantial financial backing, highlighted the growing commercialization of the gene testing business.

The risk, however, was that business development plans were running ahead of science, while regulators were left floundering with an inadequate system of oversight.

"We still do not have a regulatory framework that can control this burgeoning field," Hogarth said.

"In the absence of such a regulatory system, we are in severe danger of losing public confidence in what is a very promising and very exciting field of science."

The field of genetic testing has been revolutionized not only by scientific breakthroughs but also by the development of smart chips from the likes of Affymetrix Inc and Illumina Inc, which can test DNA at various sites along a person's genome.

(Reporting by Ben Hirschler; Editing by Rory Channing)

By Ben Blanchard

BEIJING (Reuters) - The rate of new HIV/AIDS infections in China is slowing and is now mainly being transmitted through sex, which the government could tackle with a circumcision campaign, the health minister said on Thursday.

The country will have an estimated 50,000 new infections in 2007, compared with 70,000 in 2005, though groups like men who have sex with men are increasingly at risk, according to a report by the State Council, or Cabinet, and the United Nations.

That will mean there will be about 700,000 people living with HIV/AIDS this year in China, up from an earlier estimate of 650,000.

Of the new infections, 44.7 percent will come from heterosexual transmission, 12.2 percent from men having sex with men, and 42 percent from intravenous drug use, the report said.

In the past, most infections were caused by intravenous drug use.

"At present, the AIDS epidemic in China continues to spread, but at a slower rate," Health Minister Chen Zhu told a news conference. "Sexual transmission is now the main route for the spread of AIDS."

Chen said more focus needed to be put on traditionally marginalized groups, like the gay community and drug users, though he added condom use by sex workers had risen from 14.7 percent in 2001 to 41.4 percent last year.

Yet the report found risky behavior by men who have sex with men remained widespread, with just a third using condoms for anal sex.

Chen said that with infections now primarily coming via sexual transmission, a male circumcision campaign could not be ruled out in China.

Studies have shown that circumcision could reduce the risk of HIV infection by up to 60 percent, though it does not offer total protection from the virus.

The World Health Organisation has already recommended it as one of the ways developing countries, especially in Africa, could use to fight the spread of AIDS.

"This is a technical question. I think our experts will evaluate it," Chen later told Reuters. "Even before the AIDS era some children in China were already being circumcised."

Circumcision rates are low in China compared to Asian countries like South Korea or Japan, where the foreskin is often removed at birth for hygiene reasons, or Muslim countries like Indonesia which practice it for religious reasons.

China's Muslim minority, concentrated in the far western region of Xinjiang, likewise circumcise their male children, normally as they reach puberty.

Chen said that were the government to decide to promote circumcision among the wider population, he did not think it would run into much opposition or cultural problems.

"As long as there is evidence it is effective, I don't think it would be an issue," he said.

(Editing by Jeremy Laurence)

By Julie Steenhuysen

CHICAGO (Reuters) - After 25 years of successive increases, obesity rates in the United States are holding steady, government health officials said on Wednesday.

But Americans are still plenty fat, with more than a third of U.S. adults found to be obese in 2005-2006, according to a report by the U.S. Centers for Disease Control and Prevention.

That amounts to about 72 million people in the United States, about the same as a 2003-2004 report.

"What we can be optimistic about is we haven't seen a giant increase in the last couple of years," said Cynthia Ogden, an epidemiologist for the CDC's National Center for Health Statistics. "But we aren't seeing any decrease, that's for sure."

The CDC defines obesity as a body mass index -- calculated from a person's weight and height -- of 30 or greater.

Ogden said women in the past were more likely to be obese than men, but that picture appears to have changed.

"It's a different story for men and women," she said in a telephone interview. "It used to be that women were more likely to be obese than men. Now, that is not true anymore."

Ogden said obesity rates in women have changed little since the 1999-2000 survey, but obesity rates in men have continued to rise. "Men are catching up to women," she said.

About 35.3 percent of women and 33.3 percent of men were considered obese in the 2005-2006 survey, which is statistically about even.

RACIAL, ETHNIC DISPARITIES

Obesity was most common among adults aged 40 to 59. About 40 percent of men in this age range were obese versus 28 percent of men 20 to 39.

Some 41 percent of women 40 to 59 were obese, compared with 30.5 percent of women in the 20 to 39 age range.

While obesity rates appear to be leveling off, the report shows that Americans on the whole are heavier, and people who are the fattest are much heavier than they were in 1980.

The researchers also found widespread racial and ethnic disparities.

Non-Hispanic black and Mexican-American women have higher rates of obesity than non-Hispanic white women. About 53 percent of black women and 51 percent of Mexican-American women aged 40 to 59 were obese, compared with 39 percent of white women of the same age.

And doctors still seem to consider obesity a delicate subject, the report found, with just 65 percent of obese people reporting that their doctors or other health providers ever told them they were overweight.

Doctors also seem more inclined to let men off the hook, with more women than men reporting they had been told they were too fat by a health provider, Ogden said.

That is an important message because obesity can lead to a host of health problems, including heart disease, some cancers and type 2 diabetes.

(Editing by Will Dunham and Xavier Briand)