Study Finds New Genes That Can Cause Autism

A team of international researchers claimed to have discovered an array of new genesdefine that may cause autism, a chronic and often severe disorder of brain functioning that begins during childhood.

Autism is a brain development disorder that impairs social interaction and communication and causes restricted and repetitive behavior, all starting before a child is three years old.

The research, carried out by the National Institute of Mental Health (NIMH), suggests that that some cases of autism arise from defects in genesdefine that can be activated or deactivated by mental activity, indicating that autism is not only caused by the deletion of some genes but also by turning off other genes.

"We are encouraged that some of these mutations do not seem to completely remove the gene altogether, but instead disrupt its on/off switches," said study leader Christopher A. Walsh, MD, PhD, chief of genetics at Children's Hospital Boston and an investigator at the Howard Hughes Medical Institute.

Walsh and colleagues, who studied families where parents are closely related, said they have identified at least six genes that have tied to the development of autism. They studied 104 traditional Muslim families with at least one autistic child. These families were enrolled in the Homozygosity Mapping Collaborative for Autism in the Arab Middle East, Turkey and Pakistan.

Of those Autism-linked families, 88 were headed by parents who were cousins, boosting the chances of an inherited DNA change in brain that might be related to autism in the children. Scientists say that marriages between first cousins increase the prevalence of neurological birth defects by about 100 percent.

After tracking the data, the researchers found that only one gene, “c3orf58”, was actually missing in an autistic child. Consequently, they suggested it should be renamed “deleted in autism-1", or “DIA1”.

The researchers, however, detected the five other genes, “NHE9”, “PCDH10”, “contactin-3”, “RNF8” and “SCN7A”, near deleted regions of DNA.

Besides a combination of faulty DNA, the autism is caused by the physical or social environment that a child is in after they are born, the study revealed.

Researchers now believe that groundbreaking findings, published in the July 11 issue of Science, can provide new hope for future treatment for families prone to autism.

Although the findings are of much significance, but the researchers recommend for larger studied in order to find treatment for this mental disorder.

"We still don't understand the underlying genetics for more than half the kids with autism, so we have a long way to go to understand that, and to understand what non-genetic factors might also contribute," Walsh says. "We know genetics is very, very important in autism, but we don't know whether it is the whole answer or not."

A study by CDC revealed that as many as 1 in every 150 children in the United States has autism or a related disorder. Autism is a lifelong disorder that interferes with the ability to understand what is seen, heard, and touched. The chances of occurrence of this chronic and often severe disorder of brain functioning are four times higher in boys than in girls.