Experts Say DNA Match Is Likely a Parent or Child

While federal officials said that analysis of DNA from several relatives helped confirm that it was Osama bin Laden who was killed in the military raid on Sunday, they have not yet disclosed the relationships of the family members whose DNA was used.

Officials said they collected multiple DNA samples from Bin Laden’s relatives in the years since the Sept. 11 attacks. And they said the analysis, which was performed the day Bin Laden was killed but after his body was buried at sea, confirmed his identity with 99.9 percent accuracy.

Some scientific experts said on Monday that if results really were so accurate, at least one of the sources was likely to have been a close relative, like a child or parent with whom he shared half his genes.

“That would be most likely,” said Frederic Zenhausern, director of the Center for Applied NanoBioscience and Medicine at University of Arizona.

DNA matching usually involves obtaining genetic material from a blood sample or cheek swab.

The vast majority of a person’s DNA sequence will be the same as every other person’s. So a test, which can be done in a few hours if needed, typically focuses on a small number of locations on the genome, usually 13 to 16 spots. These spots are located on what is sometimes referred to as junk DNA, areas of genetic material that do not contain instructions for building brain, bone and muscle.

A DNA analysis looks for patterns of two or more nucleotides, the chemicals that form DNA. These strings of nucleotides are called short tandem repeats. The closer the relative, the more the pattern of repeats matches. In an identical twin, they should be the same. A parent and child should share half the number of repeats. In siblings, the combinations can vary; in half-siblings, they can vary even more.

“With a sibling, there is only a likelihood that you’ll share some DNA with them,” said Mitchell Holland, a forensic scientist at Penn State University and former head of the Armed Forces DNA Identification Laboratory. “With a half-sibling, that complicates things even farther.”

Bin Laden did not have any full siblings. He did have more than 50 half-siblings, some of whom have close ties to the United States and had long ago distanced themselves from him. Dr. Zenhausern said using a half-sibling’s DNA could still yield a reasonably high chance of identification, more than 90 percent. And collecting DNA from several half-siblings would increase the likelihood of making a match.

“If you have that, you can attempt to reconstruct the parents,” Dr. Holland said. “You know the numbers the proof is coming from. But the math is relatively complex.”

If two people share a rare DNA pattern, it makes it more likely that they are related. And testing can also be taken to a more detailed level — for example, by looking at the Y-chromosome, which only males have.

Recently, some law enforcement agencies have begun using relatives’ DNA to help identify suspects in criminal cases. In 2008, California changed state law to allow use of familial DNA, relying on it last year to arrest Lonnie D. Franklin Jr., accused of being the “Grim Sleeper,” a serial killer of 11 women. A match between DNA found at the crime scene and DNA from Mr. Franklin’s son, who was arrested for unrelated weapons charges, led police to Mr. Franklin.

ABC News reported on Sunday that to identify Bin Laden, officials used DNA from the brain of a half-sister who had died at Massachusetts General Hospital in Boston. A spokeswoman for Massachusetts General said the hospital had not been able to verify that report.

“We have not been able to confirm any of this with anybody here,” said the spokeswoman, Kristen Stanton. She added, “I don’t know the name of this sister — whether it was Bin Laden or something else — but nobody we can find knows if someone who was Bin Laden’s sister was ever here.”

 

Experts Say DNA Match Is Likely a Parent or Child

While federal officials said that analysis of DNA from several relatives helped confirm that it was Osama bin Laden who was killed in the military raid on Sunday, they have not yet disclosed the relationships of the family members whose DNA was used.

Officials said they collected multiple DNA samples from Bin Laden’s relatives in the years since the Sept. 11 attacks. And they said the analysis, which was performed the day Bin Laden was killed but after his body was buried at sea, confirmed his identity with 99.9 percent accuracy.

Some scientific experts said on Monday that if results really were so accurate, at least one of the sources was likely to have been a close relative, like a child or parent with whom he shared half his genes.

“That would be most likely,” said Frederic Zenhausern, director of the Center for Applied NanoBioscience and Medicine at University of Arizona.

DNA matching usually involves obtaining genetic material from a blood sample or cheek swab.

The vast majority of a person’s DNA sequence will be the same as every other person’s. So a test, which can be done in a few hours if needed, typically focuses on a small number of locations on the genome, usually 13 to 16 spots. These spots are located on what is sometimes referred to as junk DNA, areas of genetic material that do not contain instructions for building brain, bone and muscle.

A DNA analysis looks for patterns of two or more nucleotides, the chemicals that form DNA. These strings of nucleotides are called short tandem repeats. The closer the relative, the more the pattern of repeats matches. In an identical twin, they should be the same. A parent and child should share half the number of repeats. In siblings, the combinations can vary; in half-siblings, they can vary even more.

“With a sibling, there is only a likelihood that you’ll share some DNA with them,” said Mitchell Holland, a forensic scientist at Penn State University and former head of the Armed Forces DNA Identification Laboratory. “With a half-sibling, that complicates things even farther.”

Bin Laden did not have any full siblings. He did have more than 50 half-siblings, some of whom have close ties to the United States and had long ago distanced themselves from him. Dr. Zenhausern said using a half-sibling’s DNA could still yield a reasonably high chance of identification, more than 90 percent. And collecting DNA from several half-siblings would increase the likelihood of making a match.

“If you have that, you can attempt to reconstruct the parents,” Dr. Holland said. “You know the numbers the proof is coming from. But the math is relatively complex.”

If two people share a rare DNA pattern, it makes it more likely that they are related. And testing can also be taken to a more detailed level — for example, by looking at the Y-chromosome, which only males have.

Recently, some law enforcement agencies have begun using relatives’ DNA to help identify suspects in criminal cases. In 2008, California changed state law to allow use of familial DNA, relying on it last year to arrest Lonnie D. Franklin Jr., accused of being the “Grim Sleeper,” a serial killer of 11 women. A match between DNA found at the crime scene and DNA from Mr. Franklin’s son, who was arrested for unrelated weapons charges, led police to Mr. Franklin.

ABC News reported on Sunday that to identify Bin Laden, officials used DNA from the brain of a half-sister who had died at Massachusetts General Hospital in Boston. A spokeswoman for Massachusetts General said the hospital had not been able to verify that report.

“We have not been able to confirm any of this with anybody here,” said the spokeswoman, Kristen Stanton. She added, “I don’t know the name of this sister — whether it was Bin Laden or something else — but nobody we can find knows if someone who was Bin Laden’s sister was ever here.”

 

Drumbeat of Nuclear Fallout Fear Doesn’t Resound With Experts

The fear is unwarranted, experts say. People in Japan near the Fukushima Daiichi nuclear power plant may have reason to worry about the consequences of radiation leaks, scientists say, and some reactor workers, in particular, may suffer illness. But outside of Japan, the increase is tiny, compared with numerous other sources of radiation, past and present.

Experts say that humans are bombarded by so much radiation from so many other sources, including many natural ones, that the uptick from Japan disappears as a cause of concern the big picture is considered.

That perspective suggests a human population and a global environment in which exposure to radiation is constant and significant. For example, people around the globe were exposed to radioactive fallout from hundreds of nuclear bomb test explosions in the atmosphere during the cold war. Today, medical patients choose to be exposed to regular doses of radiation from millions of X-rays and CT scans.

In the world’s oceans, thousands of decomposing drums of radioactive waste pose bigger dangers than the relatively small amounts of radioactive water released from the Fukushima Daiichi plant. And natural radiation from rocks, cosmic rays and other aspects of the environment, experts say, represents the biggest factor of all — far bigger than all the man-made emissions, including the current increase from the crippled Japanese reactors.

“It disappears as a contributor to population radiation doses,” said Frank N. von Hippel, a nuclear physicist who advised the Clinton administration and now teaches at Princeton University. But the fear of radiation is different. “Somehow,” Dr. von Hippel added, “nuclear things get stigmatized relative to their statistical risks.”

After the Japanese disaster began on March 11, blogs warned of government conspiracies to cover up radiation dangers, and public-interest groups sounded alarms.

Dr. Dale Dewar, executive director of Physicians for Global Survival, a group that advocates the abolition of nuclear arms, said the accident meant future generations would live in a world with higher levels of background radiation.

“Your hair won’t fall out,” she told an interviewer at the Vancouver Sun. “But ‘No immediate danger’ is an easy way for the nuclear industry to duck the long-term effects.”

Even Washington got the jitters. On March 15, four days after the disaster’s start, the surgeon general, Regina M. Benjamin, said it was no overreaction for Americans to stock up on iodine pills. “It’s a precaution,” Dr. Benjamin told a television interviewer.

Her office backpedaled two days later, after President Obama said Americans needed to take no protective measures.

“Most people don’t have a good handle on the risks,” Dr. Fred A. Mettler Jr., professor of radiology at the University of New Mexico and the American representative to a United Nations panel on radiation assessment, said in an interview. “They don’t know the magnitude of the sources, so they don’t know how to put the risks in perspective.”

The jargon doesn’t help. Radiation is measured in obscure units that change significantly depending on the strength of the radiation and whether the units characterize radioactivity itself, or the interaction of the radiation with the human body. Radioactive sources are said to emit curies or becquerels of radiation, but the effect on living things is measured in sieverts or rem (for “roentgen equivalent man” — it’s true).

Given what may appear to be chaotic or incomplete information, people may base their perceptions of atomic risk on a volatile mix of sensational reports and instincts.

“Risk resides mostly as a feeling,” said Paul Slovic, a pioneer of nuclear psychology at the University of Oregon. “It’s a quick gut reaction often triggered by an image,” especially ones in the movies and on television.

Dr. Mettler said, “Children in the United States are inundated with all kinds of nonsense on television from the time they are 6 months old.” Cartoon characters like the Incredible Hulk, Spider-Man and Homer Simpson, he said, all of whom experience scientifically impossible but highly entertaining effects of radiation, tend to provide most of the nation’s “radiation biology lessons.”

Dr. Slovic cited medical radiation as an example of variability in risk perception. Many experts see the public as getting a potentially risky overdose. But the public tends to think otherwise, he said. “We’re very tolerant of exposure,” Dr. Slovic said in an interview. “We want it or need it, so we feel it’s a strongly beneficial technology. And so the sense of risk is depressed.”

 

Medical Experts Dispute a Hospital’s Claims on Heart Device Data

This month, University Medical Center of Southern Nevada said in a statement, “results to date show significantly improved outcomes for our cardiac patients” who got heart implants made by a little-known company, Biotronik. The statement was attributed to Kathleen Silver, the chief executive of the hospital.

Ms. Silver issued that statement after an article in The New York Times reported that cardiologists there switched in 2008 to using Biotronik devices after that company started paying them thousands of dollars in consulting fees.

A hospital spokeswoman later said in response to a reporter’s question that Ms. Silver’s comments were based on data drawn from a national registry of heart patients who received an implanted defibrillator. University Medical Center also provided The Times with limited data from that registry that it said backed its contention.

But several experts knowledgeable about that defibrillator database said in separate interviews that it did not track how device recipients fared after they left a hospital. As a result, it cannot and does not provide data to hospitals or manufacturers about the long-term performance of any company’s device. It also does not produce data that can be used to compare the performance of competing implants made by different companies.

“To saying that we are doing better is a bridge too far for the data they have,” said Dr. Jeptha Curtis, an assistant professor of medicine at Yale, who has worked on research studies involving registry data.

Told of the experts’ assessments, Danita Cohen, the spokeswoman for the Las Vegas hospital, responded in writing by stating, “By way of clarification, U.M.C. did not intend to say that our better outcomes can be attributed to a particular device.”

She added that the hospital’s remarks about “improving patient outcomes” were intended to mean that its use of the defibrillator database was helping it monitor its performance.

The hospital’s disputed claims may intensify scrutiny of the ties between the Las Vegas physicians, Biotronik and a company called Western Medical that acts as the company’s sales representative in Nevada and several other states. Those ties are currently under review by state officials in Nevada. The Justice Department started a separate investigation last year into Biotronik’s sales and marketing practices.

The Times article focused on relationships between a device industry sales official named Caesar Fonte and cardiologists at a Las Vegas practice, Nevada Heart and Vascular. Before 2008, when Mr. Fonte worked at Boston Scientific, a defibrillator producer, the same cardiologists were paid consultants to that company and almost exclusively used its devices, hospital data shows.

Then in 2008, Mr. Fonte quit Boston Scientific and started Western Medical, the Biotronik distributor. The implant specialists at Nevada Heart and Vascular then became paid consultants to Biotronik and switched to using its devices in nearly all patients.

Both Biotronik, the physicians and Mr. Fonte have rejected any suggestion that the consulting fees were inducements to get them to use the company’s devices.

The defibrillator database is part of the National Cardiovascular Data Registry, a project run by the American College of Cardiology Foundation, in conjunction with a professional medical group, the Heart Rhythm Society. It is often referred to as the ICD registry, which is short for implantable cardioverter-defibrillator, the device’s formal name.

In 2004, Medicare mandated the creation of a national ICD registry as a condition for approving payments for defibrillators for a new class of patients, for whom evidence of a benefit was equivocal. Implant makers, who have realized vastly added sales from the Medicare ruling, supported the registry for one year then cut back financing. Its is now underwritten by hospitals, but limited financing has restricted the data it can collect.

Essentially, during a procedure to implant a defibrillator, information is collected about areas like a patient’s heart function and other medical conditions. If an existing defibrillator is being replaced by a new one, a hospital can also indicate one of several reasons why such a replacement is being performed.

The information from the national ICD registry provided by University Medical Center to The Times reflected data from two of those device replacement fields. It showed that for a four-year period between 2007 and 2010, no device had been replaced at University Medical Center because it had been recalled or because it had malfunctioned.

Earlier, when providing the data, Ms. Cohen, the hospital spokeswoman, said that its results were “highly significant” when compared with the national average for such replacement reasons. The hospital added that Biotronik has not issued any recent device recalls.

Experts like Dr. Curtis said, however, that the hospital’s data was effectively meaningless because there was no way of knowing from it whether a device being replaced at U.M.C. had been initially implanted there, or whether devices implanted at U.M.C. were later replaced elsewhere.

“If they are thinking that no news is good news from the registry, then they are misunderstanding what function the registry is performing,” said another registry expert at Yale, Dr. Harlan Krumholz.

The national ICD registry does report back to hospitals about in-hospital complication rates related to device implantation procedures so they can compare it with the national average. Asked for its complication rate, U.M.C. declined to release it.

 

Medical Experts Dispute a Hospital’s Claims on Heart Device Data

This month, University Medical Center of Southern Nevada said in a statement, “results to date show significantly improved outcomes for our cardiac patients” who got heart implants made by a little-known company, Biotronik. The statement was attributed to Kathleen Silver, the chief executive of the hospital.

Ms. Silver issued that statement after an article in The New York Times reported that cardiologists there switched in 2008 to using Biotronik devices after that company started paying them thousands of dollars in consulting fees.

A hospital spokeswoman later said in response to a reporter’s question that Ms. Silver’s comments were based on data drawn from a national registry of heart patients who received an implanted defibrillator. University Medical Center also provided The Times with limited data from that registry that it said backed its contention.

But several experts knowledgeable about that defibrillator database said in separate interviews that it did not track how device recipients fared after they left a hospital. As a result, it cannot and does not provide data to hospitals or manufacturers about the long-term performance of any company’s device. It also does not produce data that can be used to compare the performance of competing implants made by different companies.

“To saying that we are doing better is a bridge too far for the data they have,” said Dr. Jeptha Curtis, an assistant professor of medicine at Yale, who has worked on research studies involving registry data.

Told of the experts’ assessments, Danita Cohen, the spokeswoman for the Las Vegas hospital, responded in writing by stating, “By way of clarification, U.M.C. did not intend to say that our better outcomes can be attributed to a particular device.”

She added that the hospital’s remarks about “improving patient outcomes” were intended to mean that its use of the defibrillator database was helping it monitor its performance.

The hospital’s disputed claims may intensify scrutiny of the ties between the Las Vegas physicians, Biotronik and a company called Western Medical that acts as the company’s sales representative in Nevada and several other states. Those ties are currently under review by state officials in Nevada. The Justice Department started a separate investigation last year into Biotronik’s sales and marketing practices.

The Times article focused on relationships between a device industry sales official named Caesar Fonte and cardiologists at a Las Vegas practice, Nevada Heart and Vascular. Before 2008, when Mr. Fonte worked at Boston Scientific, a defibrillator producer, the same cardiologists were paid consultants to that company and almost exclusively used its devices, hospital data shows.

Then in 2008, Mr. Fonte quit Boston Scientific and started Western Medical, the Biotronik distributor. The implant specialists at Nevada Heart and Vascular then became paid consultants to Biotronik and switched to using its devices in nearly all patients.

Both Biotronik, the physicians and Mr. Fonte have rejected any suggestion that the consulting fees were inducements to get them to use the company’s devices.

The defibrillator database is part of the National Cardiovascular Data Registry, a project run by the American College of Cardiology Foundation, in conjunction with a professional medical group, the Heart Rhythm Society. It is often referred to as the ICD registry, which is short for implantable cardioverter-defibrillator, the device’s formal name.

In 2004, Medicare mandated the creation of a national ICD registry as a condition for approving payments for defibrillators for a new class of patients, for whom evidence of a benefit was equivocal. Implant makers, who have realized vastly added sales from the Medicare ruling, supported the registry for one year then cut back financing. Its is now underwritten by hospitals, but limited financing has restricted the data it can collect.

Essentially, during a procedure to implant a defibrillator, information is collected about areas like a patient’s heart function and other medical conditions. If an existing defibrillator is being replaced by a new one, a hospital can also indicate one of several reasons why such a replacement is being performed.

The information from the national ICD registry provided by University Medical Center to The Times reflected data from two of those device replacement fields. It showed that for a four-year period between 2007 and 2010, no device had been replaced at University Medical Center because it had been recalled or because it had malfunctioned.

Earlier, when providing the data, Ms. Cohen, the hospital spokeswoman, said that its results were “highly significant” when compared with the national average for such replacement reasons. The hospital added that Biotronik has not issued any recent device recalls.

Experts like Dr. Curtis said, however, that the hospital’s data was effectively meaningless because there was no way of knowing from it whether a device being replaced at U.M.C. had been initially implanted there, or whether devices implanted at U.M.C. were later replaced elsewhere.

“If they are thinking that no news is good news from the registry, then they are misunderstanding what function the registry is performing,” said another registry expert at Yale, Dr. Harlan Krumholz.

The national ICD registry does report back to hospitals about in-hospital complication rates related to device implantation procedures so they can compare it with the national average. Asked for its complication rate, U.M.C. declined to release it.