Dna

Teas from across the globe are becoming more and more popular in the U.S. One relative newcomer, yerba mate, is attracting fans for its allegedly jitter-free caffeine boost and high antioxidant content. Lab research suggests some potential health benefits from drinking yerba mate, but studies of lifelong yerba mate drinkers in the tea's native South America suggest the brew increases the risk of some cancers -- a fact most marketing campaigns omit.

Investigators don't know where 15-year-old Sierra LaMar is, but they are almost certain she is dead. For more than two months, the high school cheerleader's family has been holding out hope. They have organized repeated searches of the Northern California neighborhood where she disappeared and made numerous public appeals for help. On Tuesday, even as authorities announced the arrest of a 21-year-old suspect on suspicion of murder, Marlene LaMar vowed not to stop looking for her daughter.

Before John Lennon imagined "living life in peace," he conjured "no heaven … / no hell below us …/ and no religion too. " No religion: What was Lennon summoning? For starters, a world without "divine" messengers, like Osama bin Laden, sparking violence. A world where mistakes, like the avoidable loss of life in Hurricane Katrina, would be rectified rather than chalked up to "God's will. " Where politicians no longer compete to prove who believes more strongly in the irrational and untenable.

WASHINGTON - More than 2,000 people have been freed from prison since 1989 after they were found to have been wrongly convicted of serious crimes, according to a new National Registry of Exonerations compiled by University of Michigan Law School and Northwestern University. Its sponsors say it is by far the largest database of such cases, and they hope it will help reveal why the criminal justice system sometimes misfires, prosecuting and convicting the innocent. "The more we learn about false convictions, the better we'll be at preventing them," said Samuel Gross, a University of Michigan law professor.

Bob Kahl slips in through a side door of the vast, abandoned hangar and looks at what's left of the assembly plant where he worked for nearly 40 years. He remembers the hum of power tools, the biting aroma of cutting oil, swarms of workers plugging away on a labyrinth of yellow scaffolding. All that's left is a few piles of broken concrete and a sea of colorless dust that coats a Palmdale factory floor the size of two football fields. "Welcome to the birthplace of America's space shuttle fleet," said Kahl, 60, smiling.

The most enduring and romantic legend of the Russian Revolution -- that two children of Czar Nicholas II and his wife, Alexandra, survived the slaughter that killed the rest of their family -- may finally be put to rest with the positive identification of bone fragments from a lonely Russian grave.

Marilyn Vann can trace her Cherokee roots back more than 200 years through generations of Native Americans and the descendants of black slaves who lived among them. She has mountains of paper -- birth certificates, tribal enrollment cards, land deeds, affidavits, yellowing photographs -- documenting her family's life within the tribe.

Children who are exposed to violence experience wear and tear to their DNA that is similar to that seen in aging, according to a new study that may help explain why they face a heightened risk of mental and physical disorders as adults. In a long-term study of 118 pairs of identical twins, researchers at Duke University found that boys and girls who had experienced violence had shorter genetic structures called telomeres than youngsters who had more peaceful upbringings. The children in the former group had been physically abused by an adult or bullied frequently, or had witnessed domestic violence between the ages of 5 and 10. And the more types of violence a child had experienced, the faster his or her telomeres eroded, said study leader Idan Shalev, who published the findings Tuesday in the journal Molecular Psychiatry.

Today, a century and a half after Charles Darwin published "On the Origin of Species by Means of Natural Selection," the overwhelming majority of scientists in the United States accept Darwinian evolution as the basis for understanding how life on Earth developed. But although evolutionary theory is often portrayed as antithetical to religion, it has not destroyed the religious faith of the scientific community. According to a survey of members of the American Assn. for the Advancement of Science, conducted by the Pew Research Center in May and June this year, a majority of scientists (51%)

Paul House, a Tennessee death row inmate, was just one vote away from possible execution when a divided Supreme Court said three years ago that new DNA evidence called for reopening his case. The Tennessee Supreme Court already had rejected his appeals, as had the U.S. Court of Appeals in Cincinnati.

His last letter home to his father is written in tight script on paper that has yellowed. It's dated Feb. 20, 1944. "Just a line Dad to say goodbye and don't worry too much," wrote Marine 1st Lt. Laverne A. Lallathin, 22. "I'm going over to end this thing as soon as possible. Buy as many bonds as you can and pray that I will be all-right. " A month later, Lallathin vanished along with six crew members of the B-25 bomber he was piloting from Espiritu Santo, the largest island in the South Pacific nation of Vanuatu.

DALLAS - On the way to witness his first execution in the town known as the "Execution Capital of the World," the Dallas County district attorney stopped at the prison cemetery to find his great-grandfather's grave. Captain Joe Byrd Cemetery in Huntsville is the final resting place of inmates whose families could not afford burial anywhere else. Tall pines guard the grassy expanse nicknamed "Peckerwood Hill," where many gravestones bear prison identification numbers, not names.

Though the indigenous people of the Solomon Islands all have dark skin, about 5% to 10% also have naturally blond hair - and a new study finds that the genetic quirk responsible for this is different from the one that produces blond hair in people of European ancestry. Researchers from Stanford University and colleagues collected spit samples from 43 Solomon Islanders with blond hair and 42 with the darkest hair. They scanned the DNA in all of the samples and looked for telltale differences that were linked with hair color.

Analyzing DNA from four ancient skeletons and comparing it with thousands of genetic samples from living humans, a group of Scandinavian scientists reported that agriculture initially spread through Europe because farmers expanded their territory northward, not because the more primitive foragers already living there adopted it on their own. The genetic profiles of three Neolithic hunter-gatherers and one farmer who lived in the same region of...

For nine years the "teardrop" rapist was one of Los Angeles' most prolific serial predators, preying on women from Melrose Avenue to Manchester Boulevard. The assailant, sometimes described as having a teardrop tattoo below one of his eyes, targeted girls and women walking alone in the early-morning hours. He would force them into a secluded area at the point of a gun or knife before raping or sexually assaulting them. There were 27 reported rapes or attempted assaults between 1996 and 2005.

Children who are exposed to violence experience wear and tear to their DNA that is similar to that seen in aging, according to a new study that may help explain why they face a heightened risk of mental and physical disorders as adults. In a long-term study of 118 pairs of identical twins, researchers at Duke University found that boys and girls who had experienced violence had shorter genetic structures called telomeres than youngsters who had more peaceful upbringings. The children in the former group had been physically abused by an adult or bullied frequently, or had witnessed domestic violence between the ages of 5 and 10. And the more types of violence a child had experienced, the faster his or her telomeres eroded, said study leader Idan Shalev, who published the findings Tuesday in the journal Molecular Psychiatry.

Women may soon be able to find out very early in their pregnancies whether they are carrying a fetus with Down syndrome by offering a simple blood sample. The safe, noninvasive test would pose fewer risks to the mother and fetus than amniocentesis or chorionic villus sampling (CVS), the two tests currently used for prenatal diagnosis. It would also give women more time to decide what to do if a diagnosis of Down syndrome is made. Researchers from the Chinese University of Hong Kong have been working on the DNA-based test for a decade.

The Times is to be commended for its well-taken points in its editorial (May 14) regarding the implications and importance of mapping the human genome. However, the big picture presented was marred by a few critical details. The corrections stand as follows. DNA is not a sequence of amino acids, but rather a sequence of nucleotides, each of which consists of (1) a ribose sugar, (2) a phosphate, and (3) a nitrogen-containing base, which may or may not be an amino acid. The importance of these corrections is that of clarifying the distinction between proteins, which are indeed sequences of amino acids, and nucleic acids (DNA is one)

The very title of the subversive documentary "Surviving Progress" sounds counterintuitive. Isn't progress a good thing, the sure cure for civilization's ills? What's to survive? Plenty, according to this expect-the-unexpected Canadian film based on Ronald Wright's bestselling "A Short History of Progress. " Both brainy and light on its feet, bristling with provocative insights and probing questions, this film feels like it's expanding your mind while you're watching it. The premise of "Surviving Progress," much more dystopian in its quiet way than "The Hunger Games," is that we delude ourselves if we think the seeming improvements that growth and development bring will result in quality-of-life advances or even survival of the planet.

DNA and RNA molecules are the basis for all life on Earth, but they don't necessarily have to be the basis for all life everywhere, scientists have shown. Researchers at the Medical Research Council in Cambridge, England, demonstrated that six synthetic molecules that are similar to - but not exactly like - DNA and RNA have the potential to exhibit "hallmarks of life" such as storing genetic information, passing it along and undergoing evolution. The man-made molecules are called "XNAs.