Abstracts
The genetic basis of intellectual disability
Tod Fullston.
PhD Student, University of Adelaide, Discipline of Paediatrics
Supervised through Genetic Medicine, CYWHS
Intellectual disability (ID) is common in the Australian population, estimated to occur in up to 1 in every 50 people. Mutations in the'ARX' gene cause a broad range of pathologies, all of which include ID. We undertook the largest screening of the ARX gene ever undertaken, of 500 individuals with ID, to establish what contribution ARX mutations make to ID. Thirteen mutations were detected in total, with ten of the thirteen mutations occurring within the same section of the gene. Five of the mutations had not been previously discovered. Of the new mutations discovered, one causes a type of severe and early onset epilepsy (Ohtahara syndrome), this is the first time a mutation in any gene has been shown to be responsible for this disorder. We have shown that mutations in the ARX gene significantly contribute to ID and epilepsy. Studying mutations in the ARX gene not only provide useful genetic information for the families involved, but also give insight to how the ARX gene functions when it is not mutated.
