Toga To Be Used In Study Of Epileptic-Type Seizures

Digital Gene Technologies Inc.'s Toga gene expression profiling technology has been selected for a groundbreaking investigation into molecules associated with epileptic seizures. Professor Stephen Heinemann and Dr. Andreas Sailer of the Salk Institute for Biological Sciences (La Jolla, CA) will conduct the study.

In their experimental protocol, Heinemann and Sailer will use Toga (TOtal Gene expression Analysis) to identify differentially expressed genes found in a mutant mouse strain deficient for the glutamate receptor subunit GluR6, known to be associated with epileptic-type seizures. The Toga technology was developed by Dr. J. Gregor Sutcliffe, a founder of Digital Gene and chairman of the company's scientific advisory board, at The Scripps Research Institute. It provides an inventory of gene activity in a single cell or tissue sample and defines the function of the vast array of genes comprising any genome.

"Toga analysis of GluR6-deficient mice represents a novel approach to studying the consequences of a well-defined alteration in the excitatory signaling pathway on gene expression of almost the entire genome," said Heinemann. "By using Toga to identify subtypes of receptors involved in seizure induction, we will have accomplished a major step towards defining suitable targets for the development of new epilepsy drugs."

In April of this year, Heinemann and his colleagues published results of research showing that mice lacking GluR6 exhibited reduced susceptibility to epileptic-type seizures. As part of the research, kainate was used to induce seizures in mice. Kainate, known as an analog of the naturally occurring brain transmitter glutamate, is widely used as a chemical model for human temporal lobe epilepsy because the seizures and patterns of neuronal damage it induces closely resemble those observed in epileptics. The researchers then created mice lacking GluR6 and showed that these mice were less susceptible than normal mice to kainate-induced seizures.

Glutamate is necessary for learning and memory, and its receptors are found throughout the brain. However, all glutamate receptors are not identical and can be sorted into subtypes based on subtle differences, such as those associated with seizure induction. It is these subtypes that Toga will be used to identify, thereby establishing targets for new drugs which may block GluR6 and prevent the seizures and brain damage they cause.

For more information: Robert J. Sutcliffe, president and chief executive officer, Digital Gene Technologies Inc., telephone: 619-552-1400.