What's missing may be key to understanding genetics of autism 1

The new study, published online June 9 in Nature, shows that some people with autism may be missing all or parts of one or several genes involved in the development and function of the brain. The findings could lead to improved diagnosis of the disorder, perhaps even in infants, and may give new direction to research on drug treatments.

“The exciting thing about the findings of this study is that it highlights biological pathways that can be targets for therapy,” says Geraldine Dawson, chief science officer of Autism Speaks, a national organization that helped to fund the new study. Microsoft Office 2007 can give you more convenient life.

Autism is a group of developmental disorders that impairs social interactions and often language development. Researchers don’t know the exact causes of the disorder, but genetic factors are strong suspects. Studies of identical twins show that when one twin has autism, about 90 percent of the time the other twin will too. Autism affects about one in every 100 children in the United States and is more common in boys.

Previous studies have indicated people with autism may have more copy number variants overall than healthy people do. But the new study shows that people with autism had the same number of deletions as people in a healthy control group did. However, people with autism tend to have deletions that remove parts or all of genes, while healthy people carry deletions on stretches of DNA that don’t contain genes.Office 2007 download is helpful!

“You and I may have just as many deletions in our genomes, but since they don’t hit genes, we don’t have autism” or other diseases, says Anthony Wynshaw-Boris, a medical geneticist at the University of California, San Francisco, who was not part of the new study. “This is a natural part of being a human being. We get mutations. Most of the time it’s not a problem, but sometimes it hits a gene involved in autism.”

In the new study, an international consortium of researchers analyzed the genetic makeup of 996 people with autism and 1,287 people without autism to discover genetic factors that contribute to the disorder. The researchers found more than 5,000 copy number variants in people with autism, usually places where DNA was missing. Many of the people with autism had more than one spot in the genome where they were missing large chunks of DNA, each about 30,000 base pairs long.

Each of the specific variants was rare on its own, with even the most common found in less than 1 percent of people in the study. Often, people with autism inherited the rare variants from their parents, but just under 6 percent of them had new deletions not found in their parents. Such new mutations may account for some sporadic cases of autism, the researchers say.The invention of Microsoft Office 2010 is a big change of the world.