April 29, 2009 |
By analyzing DNA from more than 2,000 autistic children, researchers have uncovered the best evidence yet for genetic links to the disorder - all tied to the way brain cells form and dissolve connections. The research effort, led by Hakon Hakonarson at Children's Hospital of Philadelphia, used much larger samples than had been analyzed before to identify genetic differences between autistic subjects and controls. The CHOP group collaborated with Penn, UCLA, and other institutions, announcing their findings in two papers in today's issue of the journal Nature.
December 18, 2008 |
To scientists, it was a mystery. Most of the genetic material we carry in our cells seemed to have no purpose. It seemed so useless, some called it "junk DNA. " Weirder still, geneticists noticed that some of the junk has a life of its own, copying itself, viruslike, and jumping around the DNA. This phenomenon had never been documented in humans until geneticist Haig Kazazian started studying boys with the blood-clotting disorder hemophilia....
January 25, 2008 |
In a major step toward the creation of artificial life, scientists are reporting today that they assembled the entire genetic code for a simple bacterium from scratch. The technique used to duplicate a real organism's DNA could allow the fashioning of novel organisms designed to, say, pump out new biofuels or absorb carbon dioxide, the researchers said. And by exploring the boundaries between the living and inanimate worlds, the work may change our understanding of the nature of life itself.
February 25, 2007 |
Months before the FDA's December announcement that meat from cloned animals is safe to eat, employees at Cyagra in Lancaster County were carving into cloned steaks several times a week. The Elizabethtown company clones cattle, so it volunteered samples from 11 clones and 11 ordinary cattle for tests requested by the U.S. Food and Drug Administration. That left workers with a lot of leftovers, said Cyagra spokesman Steve Mower. They started with the steaks. When those ran out, they ate cloned hamburgers, tacos, lasagna and meat loaf, most of it prepared by the company's receptionist.
February 12, 2007 |
What makes you different from everyone else on the planet may have less to do with the spelling of your genetic code than with a scattering of chemical "tags" that, like censor's marks, render some of your genes unreadable. The code itself, after all, is 99.9 percent identical in all of us, so these peripheral elements - referred to as epigenetics - offer a plausible reason human beings come in such a variety of shapes and sizes. As one recent paper suggested, epigenetics can explain why identical twins don't always look identical, especially as they get older.
November 27, 2006 |
When Kari Stefansson set out to coax the secrets of the genetic code from the DNA of 100,000 volunteers, critics called the idea crazy - even unethical. Though his company has yet to turn a profit, he's proved himself to the scientific world with a series of findings connecting genes to 15 disorders including stroke, diabetes and asthma. His gene-hunting concept worked so well that two teams of attorneys have been fighting over it in a federal courtroom in Philadelphia for much of the fall.
October 12, 2006 |
Do you have the feeling you're related to someone famous? Maybe it's an uncanny sense that Mozart was your ancestor. Or that Genghis Khan might be in your family tree. That affinity you feel for ancient Rome can't be an accident, can it? Touring the toppled ruins of columns and friezes in the ancient city stirs something in you. Perhaps one or your ancestors was one of those emperors, or perhaps just a Roman soldier. It's in your blood. Now, with a simple swab of your cheek and a few hundred dollars, you can find out. Commercial genetic genealogy is barely five years old, but already it is proving irresistible to many.
March 13, 2006 |
It was a nice idea that we're all genetically 99.9 percent identical, but new research says it's not so simple. The old thinking held that coiled in our cells, we all carry the same instruction book with just a few alternative spellings. But upon closer scrutiny, it appears our DNA is full of long strings of genetic code that are copied sometimes hundreds of times, the number of copies varying wildly from person to person. And each of us is apparently missing quite a few large chunks of DNA. Other large segments of genetic code are misplaced on their chromosomes or pasted in backward.
February 3, 2003 |
In the near future, individuals may be able to pinpoint which diseases they should worry most about - heart disease, Alzheimer's, stroke, prostate cancer or multiple sclerosis. The medical crystal ball will be high-tech, inexpensive, personal genetic testing, which could be available in just five to 10 years, according to some medical researchers. "This will create a profound revolution in medicine," predicts Leroy Hood, a molecular biologist at the University of Washington.
March 25, 2002 |
The $3 billion effort to unravel the human genome may eventually bring its promised revolution in medicine and fix what ails us. But tangible results may come sooner by decoding bugs. "The bottom line is that fixing things is hard - killing things is easier," said biologist David Roos, head of the Institute for Genomics at the University of Pennsylvania. Studying the genes of killer pathogens that cause infectious diseases such as TB, cholera, AIDS and malaria can help identify the microbes' weak spots.