Gene link to epilepsy and intellectual disability

A gene with links to both epilepsy and intellectual disability has been identified for the first time by researchers at the Women's and Children's Hospital in Adelaide.

The gene is found on the X Chromosome and is one of about 100 which, when mutated, can cause intellectual disability. But genetic scientist Jozef Gecz said it was different to other such genes in that it was also linked to epilepsy.

"Previously nine other epilepsy-causing genes have been identified and these belong predominantly to a specific group call ion channels and they have nothing to do with intellectual disability," Professor Gecz said.

"Our new gene is different, being more of a master gene, controlling how, where and when other genes work and thus contributing to the normal cognitive function of the human brain. It will be very interesting to know the identity of the genes that are under control of this master gene as they may potentially be involved in either epilepsy, intellectual disability or both."

Dr Gecz, who led a team of 17 researchers from six countries, said his team was puzzled by its finding that the same mutation in the newly identified gene could give rise to two very different conditions. "We studied genetic material from nine families worldwide and found the same genetic mutations gave rise to epilepsy as well as intellectual disability," he said.

"We have no answers for why this occurs but it is something we are keen to study further." Dr Gecz said his team's discovery would allow for feedback to be provided to affected families to help them make informed reproductive decisions.