From: Robina Suwol
Date: 19 Dec 2006
Remote Name: 220.127.116.11
French researchers identify gene linked to autism
Sun Dec 17, 2:43 PM ET
French researchers have discovered a new gene linked to autism, a mental disability which prevents sufferers from communicating and forming relationships normally and whose causes are unknown. The study, published Sunday online by Nature Genetics journal, found that all of five autistic children studied had anomalies in the SHANK3 gene, responsible for making the connections in the brain necessary for language development.
The most distinctive symptoms of autism are problems with communication, forming relationships and developing strong obsessional traits. The Institut Pasteur study showed "the key role of the gene in the organisation of neurone connections" in the brain, lead researcher Thomas Bourgeron told AFP. "This gene, named SHANK3, does not explain all forms of autism" warned Bourgeron, but it might help explain the communication difficulties which provide major social obstacles to many sufferers. The study sample included five people from three families, each suffering either from autism or Asperger's Syndrome. Asperger's Syndrome is an autistic spectrum disorder (ASD) which shares most of the symptoms of autism with less severe communication problems. "It (ASD) affects about one child in 200 and four times' more boys," Bourgeron said of the lifelong disorders.
In 2003, Bourgeron's team identified anomalies on SHANK3, which produces the proteins necessary to construct synapses, the junctions between the brain's neural pathways. They discovered significant "deletions" to various degrees in the gene. One participant, who was autistic but had learned to talk, was found to have a "duplicate" of the gene. The research was conducted with Paris' psychiatric services institute Inserm, and the University of Gothenberg in Sweden. Autism usually does not appear in infants before the age of three, though it can be diagnosed as early as 18 months.
Children who suffer from it display impaired social skills and communications abilities throughout their lives, and their families bear a substantial financial and emotional burden in caring for them. Global statistics on autism are limited, with figures appearing to show the disease on the rise. According to the Autism Society of America, 10 percent to 17 percent more people are diagnosed with autism each year, but this may be partly due to increasing awareness and identification of the disease.
The US Center for Disease Control estimates that between one child in 500 and one in 166 may be diagnosed with a disease on the autism spectrum. The causes of autism remain mysterious. Years of research have gone into identifying a genetic cause. US autism researcher Bernard Rimland, who died in November, courted controversy by claiming that an increase in autism diagnoses might be caused by childhood vaccinations. Research is increasingly addressing the idea that autism may be caused by a combination of genetic and environmental factors.