Patients share some common genes

Apr 29, 2009 11:02 GMT  ·  By

In a new scientific study, published in the prestigious journal Nature, US National Institutes of Health (NIH) expert Dr. Raynard Kington introduces the most compelling evidence to date that the underlying triggering factor of autism is a genetic one. Furthermore, the researcher points to a certain gene, which, if annihilated, could reduce the incidence of worldwide autism cases by more than 15 percent, the BBC reports. In previous studies, other genetic variants have been linked to the condition as well, but their influence on the final outcome of the condition is pretty insignificant. The new one, however, bears a great influence on developing and maintaining correct connections between brain cells.

“These findings establish that genetic factors play a strong role in autism spectrum disorder (ASD). Detailed analysis of the genes and how they affect brain development is likely to yield better strategies for diagnosing and treating children with autism,” Kington explained, quoted by the British news agency.

ASD also includes such conditions as autism and Asperger's syndrome. For the recent investigation, experts at the University of Pennsylvania analyzed more than 10,000 test subjects, and scanned their genomes in hopes of finding the small genetic discrepancies that favored the onset of the disease in youngsters or adults.

“Because other autism researchers have made intriguing suggestions that autism arises from abnormal connections among brain cells during early development, it is very compelling to find evidence that mutations in genes involved in brain interconnections increase a child's risk of autism. There are going to be many genes involved in causing autism. In most cases, it's likely that each gene contributes a small amount of risk, and interacts with other genes and environmental factors to trigger the onset of disease,” Dr. Hakon Hakonarson, who has been the lead researcher for the new study, further explained. He added that the genetic interactions that caused autism might yet take a few more years to be thoroughly deciphered.

The results of the genome screenings revealed that a gene called CDH10 was present in well over 65 percent of all autism cases, which led scientists to conclude that, by suppressing it, the number of worldwide autism cases could decrease by as much as 15 percent. In addition, a group of other 30 genes was found to play at least some part in the onset and development of the disease, but to a lesser extent than CDH10. Still, despite advancements in research, the main cause of autism remained unknown, the National Autistic Society said.

“There is evidence to suggest that genetic factors are responsible for some forms of autism. However, the difficulty of establishing gene involvement is compounded by the interaction of genes and by their interaction with environmental factors. Various studies over many years have sought to identify candidate genes, but so far inconclusively,” the organization stated in a press release.