Researchers at Baylor College of Medicine and the Duncan Neurological Research Institute (Duncan NRI) at Texas Children’s Hospital show that epilepsy can be caused not only by defects in a single gene, as has traditionally been considered, but also by specific combinations of two and potentially more defective genes.

The study, published in the Journal of Clinical Investigation, could lead to improvements in genetic diagnosis and treatment for many unsolved or drug-resistant cases.

“Epilepsy is a neurological condition that causes recurrent seizures and affects about 50 million people worldwide—roughly 1 in every 130 people,” said corresponding author Dr. Hugo Bellen, Distinguished Service Professor of the Department of Molecular and Human Genetics at Baylor and chair in neurogenetics at the Duncan NRI.