There is a special legacy of risk in having more than one set of DNA


Mosaicism in iris color not a problem — compared, say, to mosaicism in kidneys

When Meriel M. McEntagart, a geneticist at St. George’s University of London, met this family in May 2012, she suspected that three of the children had a rare genetic disorder called Smith-Magenis syndrome…Dr. McEntagart confirmed that diagnosis with a genetic test. The children were all missing an identical chunk of a gene known as RAI1.

One of the children had a different father from the other two, and so the mother could be the only source of their altered gene. But when Dr. McEntagart ran a standard blood test on the mother, the results were not nearly so straightforward: The woman had a normal version of RAI1.

Dr. McEntagart and her colleagues suspected that the answer to this puzzle was that the mother was a genetic mosaic.

We tend to think of ourselves as having just one set of genetic material, which exists in identical form in every one of our cells. But sometimes, people have two or more significantly different genomes. As our cells divide, some may go through a major mutation. So some individuals end up with groups of cells that have very different DNA from the rest of them.

Dr. McEntagart said that she suspected that the mother she encountered had a normal version of RAI1 in some cells but an altered version in other cells, including her eggs.

“We wanted to understand if there was a way to demonstrate that she was a mosaic,” Dr. McEntagart said…

In a study released Thursday in the American Journal of Human Genetics, the Baylor team and its colleagues describe the biggest search for cases in which mosaic parents passed down disease-causing mutations to their children. It turns out to be far from a fluke…

Michael Snyder, a geneticist at Stanford University who was not involved in the study, said it showed that mosaicism could have a significant effect on not just people’s own health, but on their children as well.

Having developed a method for detecting mosaic parents, the scientists decided to conduct a larger study to see how common mosaicism is. They began searching for families that would be willing to participate. Each family had to have a child that had a genetic disorder caused by the deletion of some DNA. And they had to have taken a standard genetic test that had failed to find the deletion in either parent’s genes.

Eventually, the scientists were able to study 100 families. They searched for cases in which the parents were mosaics and had the same mutation as their children.

“We thought going into this study we’d find maybe one or two if we were lucky,” said Ian M. Campbell, the lead author of the study. “And then we found four.”

Mr. Campbell and his colleagues were surprised to find that many mosaic parents. And they suspect that the true number of mosaics among the 100 families was even higher. For one thing, their method lets them detect only genetic deletions, but other kinds of mutations can cause genetic disorders, too.

James R. Lupski, another co-author on the study, points to a second limitation of the study. “It only tells you what you see in the blood,” he said. If the scientists could have examined muscle or other tissues, they might have found even more mosaic cells.

The results suggest that some people can have serious genetic diseases without any symptoms. That’s because they have the defective version of a gene in only some of their cells, and their other cells compensate for them.

But such people are unknowingly at risk of having children with full-blown versions of their diseases, if the mutation appears in their reproductive cells. Dr. Lupski said that as technology improved, clinical geneticists should test people for this hidden risk.

“Couples are going to want some answers,” he said.

Another benefit of modern science – unfortunately rejected by some. Equipping a happy couple to make an informed decision about whether or not to bring someone into life that may be one of unwarranted difficulty and pain is at a minimum an opportunity for choice.

Our government hands poultry inspection over to the plant owners!

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The Agriculture Department has released long-awaited poultry-inspection rules that will give plant operators the option of conducting their own inspections for bird defects and feces on the processing lines and allow government inspectors to concentrate on other food-safety issues in the plant.

Agriculture Secretary Tom Vilsack said the new rules were the most significant change in food-safety inspections in nearly 60 years. They “will increase the chances of us detecting problems by placing the burden of finding contaminates such as salmonella on the plants,” he said…

How gullible does that sound to you?

The department also announced that it would limit speeds on poultry plant lines to 140 birds per minute to protect workers from repetitive-stress injuries like carpal tunnel syndrome. The current average is about 130 birds a minute, officials said, but food-safety groups were worried because earlier proposals indicated the limit would be significantly raised.

The increase is ruled OK because the plant owners wanted to make it even worse.

“The one U.S.D.A. inspector left on the slaughter line under this new rule will still have to inspect 2.33 birds every second — an impossible task that leaves consumers at risk,” Wenonah Hauter, executive director of Food & Water Watch, said in a statement.

“This is not a meaningful victory because there are not accompanying worker-safety regulations to deal with the musculoskeletal disorders and other work-related injuries that both the plant workers and U.S.D.A. inspectors suffer every day working in the poultry slaughter plants,” she added.

Just in case you thought there was some interest in our government to protect the public and meatpacking workers from crappy working conditions, crap-laced food and crap-filled food products – our Department of Agriculture provides a public service announcement letting us know we’re on our own more than ever.

My family stopped buying chicken from the brands that raise and kill poultry as part of a grubby, unsafe packing process that treats consumers with as little care as the birds they’re harvesting. Years ago. These new rules ain’t about to change that.

CIA admits hacking Senate computers – a criminal violation of Constitution

An internal CIA investigation confirmed allegations that agency personnel improperly intruded into a protected database used by Senate Intelligence Committee staff to compile a scathing report on the agency’s detention and interrogation program, prompting bipartisan outrage and at least two calls for spy chief John Brennan to resign…

The rare display of bipartisan fury followed a three-hour private briefing by Inspector General David Buckley. His investigation revealed that five CIA employees, two lawyers and three information technology specialists improperly accessed or “caused access” to a database that only committee staff were permitted to use…

In other conclusions, Buckley found that CIA security officers conducted keyword searches of the emails of staffers of the committee’s Democratic majority _ and reviewed some of them _ and that the three CIA information technology specialists showed “a lack of candor” in interviews with Buckley’s office.

The inspector general’s summary did not say who may have ordered the intrusion or when senior CIA officials learned of it.

He didn’t confirm or deny White House knowledge of the crime.

Following the briefing, some senators struggled to maintain their composure over what they saw as a violation of the constitutional separation of powers between an executive branch agency and its congressional overseers…

The findings confirmed charges by the committee chairwoman, Sen. Dianne Feinstein, D-Calif., that the CIA intruded into the database that by agreement was to be used by her staffers compiling the report on the harsh interrogation methods used by the agency on suspected terrorists held in secret overseas prisons under the George W. Bush administration.

The findings also contradicted Brennan’s denials of Feinstein’s allegations, prompting two panel members, Sens. Mark Udall, D-Colo., and Martin Heinrich, D-N.M., to demand that the spy chief resign

Otherwise – Just fire the bum!!

RTFA for beaucoup details. Lots of anger expressed by members of Congress who normally haven’t the backbone to challenge any example of intelligence community corruption. It’s amazing how upset government creeps can become when they’re treated like the rest of us ordinary citizens.

Like many of his peers, like the present and former residents of the White House, Brennan lied to Congress and to the American people. Will Congress or Obama have the integrity to demand criminal charges be forthcoming from the DOJ and Attorney-General Holder? Hmmm. How likely does that seem to you?

Our pollution reached Antarctica before the great explorers


Lead pollution from Oz got there first

Lead pollution from Australia reached Antarctica in 1889 – long before the frozen continent’s golden age of exploration – and has remained there ever since, new research shows.

In our study, published in Nature Scientific Reports, my colleagues and I used ice core samples from West and East Antarctica to reveal the continent’s long and persistent history of heavy metal pollution.

The Antarctic remains the most remote and pristine place on Earth. Yet despite its isolation, our findings show that it has not escaped contamination from traces of industrial lead, a serious pollutant and neurotoxin. The levels of lead pollution found in the ice cores is too low to impact Antarctic ecosystems, but higher levels would be expected closer to sources…

The new study, led by Dr Joe McConnell of the Desert Research Institute in Nevada, used an array of Antarctic ice cores to reveal a detailed record of where and when pollution can be found.

The first trace of lead pollution arrived in Antarctica around 1889, 22 years before the Amundsen and Scott expeditions to the South Pole.

We also discovered that lead pollution in the Antarctic peaked twice, and that in both cases Australia was the primary source.

After an initial peak in the late 1920s, lead levels dropped in sync with the Great Depression and Second World War. The pollution peaked again in about 1975.

Today, although levels are lower than at the 1975 peak, they remain at roughly three times the pre-industrial level…

More analysis will help us unlock more of Antarctica’s secrets. If you’ll excuse the pun, our latest results are just the tip of the iceberg with regard to information stored in the Antarctic ice sheet.

For example, fires in the Southern Hemisphere have left traces in the ice and a history of climate. The history of persistent organic pollutants and mercury in the remote south are still poorly known. Colleagues at CSIRO and the Australian Nuclear Science Technology Organisation are using ice cores to understand the past variability of greenhouse gases and the Sun. Combined with records from tree rings, sediments and caves, ice cores help to recreate a large-scale reconstruction of past sea level pressure.

Meanwhile, Antarctica continues to serve as a sentinel for unintended consequences of human activities – in this case, the pollution of a pristine frozen wasteland by an Australian mining product.

Today’s abusers of the word “conservative” will continue on their plastic primrose path to the destruction of Earth’s biosphere given any opportunity at all. Unlike their predecessors – for whom conservative also meant conservator of the Earth – prattle about denial is all they have to offer their children and grandchildren when they grow old enough to accuse them of rejecting human responsibility for polluting limited resources. Including the transformation of our climate at a radical pace.

When science points out the corruption of our planet, the response of these cowards is simply to deny science.