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.”

 

Run-off election likely in Peru

。 11 April 2011 Last updated at 04:26 ET Ollanta Humala has been likened to Venezuela's left-wing President Hugo Chavez Partial results in Peru's presidential election give left-wing former army officer Ollanta Humala the lead, but without the 50% of votes needed to avoid a second round.

With 50% of votes counted Mr Humala has 27.6%, with former Prime Minister Pedro Pablo Kuczynski on 23.1%.

Keiko Fujimori, daughter of disgraced ex-leader Alberto Fujimori, has 22%.

Observers from the Organization of American States say no major logistical difficulties affected the election.

The results so far declared are mainly from cities and towns.

Full unofficial results compiled by the election watchdog Transparencia give Mr Humala a clear lead, with Ms Fujimori. If that is confirmed, there will be a run-off election for those two candidates on 5 June.

Former President Alejandro Toledo is also contesting the election.

Outgoing President Alan Garcia could not stand for a second term and his Apra party did not put forward a candidate.

Peru is enjoying an economic boom and the campaign focused on how to maintain growth while tackling widespread poverty.

'Aids or cancer'

Ollanta Humala, 48, who came second to Mr Garcia in 2006, campaigned on a promise to increase the state's role in the economy and redistribute wealth to Peru's poor majority.

Keiko Fujimori says she wants to continue her father's legacy

His critics have compared him to Venezuela's left-wing President Hugo Chavez, but he has emphasised links with Brazil's governing Workers' Party.

Keiko Fujimori, 35, appealed to voters who still admire her father, president for a decade from 1990. He is now serving a 25-year jail sentence for corruption and organising death squads.

She has defended his record, saying by taming hyper-inflation and defeating Marxist Shining Path rebels, he laid the basis for Peru's current economic boom.

The prospect of a run-off between Mr Humala and Ms Fujimori has worried some Peruvians, including the Nobel Prize-winning author Mario Vargas Llosa, who has said it would be like "choosing between Aids and cancer".

Mr Vargas Llosa is an outspoken critic of left-wing politics and himself stood for president in 1990 only to be defeated by Alberto Fujimori.

On the eve of the election, Apra gave its support to Mr Kuczynski, 72.