Researchers at Yale University have developed the first animal model of focal cortical dysplasia (FCD) that is representative of the human condition. This is a major step for our understanding and future management of the condition.FCD is a congenital abnormality of brain development (in the womb), whereby the neurons in a particular region fail to migrate to their proper location. They become ‘stuck’ in transit and grow abnormally, whilst making faulty connections with other cells. FCD is a common cause of drug-resistant epilepsy in children, and a frequent cause of epilepsy in adults.The scientists at Yale, led by Professor Angélique Bordey, have begun to use their new (mouse) model to explore the mechanisms that underlie FCD, the events that occur before and after the development of FCD-related seizures and if/when seizures can be prevented from occurring.Key to their study has been a drug called rapamycin, which is licensed as an immunosuppressant and also plays an important role in controlling abnormal cell growth and proliferation. The team treated their FCD animals with rapamycin both before and after birth, and found that, even when given after birth, the drug was able to disrupt the ‘dysplastic’ processes and prevent seizures from developing. They also observed, however, that rapamycin treatment had to be continued in order for its effects to be maintained.Both of these findings have been reported before, but they needed to be confirmed in a model that was more representative of human FCD. It remains to be established, however, if treatment with rapamycin can stop seizures once they are already occurring, and the new model is likely to be instrumental in this.So why not give children who have FCD rapamycin after birth to prevent the onset of seizures? Unfortunately, a major disadvantage of this drug is that it can have significant adverse effects on cognitive development. This was seen in the new model, and it has also been reported in trials of rapamycin for children with tuberous sclerosis (a condition closely related to FCD).The hope is that the new model of FCD will ultimately allow scientists to develop novel treatments that prevent seizure development in a targeted way, with fewer unwanted side effects. This would have an enormous impact on the quality of life, and life expectations, of those with FCD.This study is published in Nature Communications.Click here to watch a video interview with Professor Bordey, in which talks about the work being carried out in her laboratory.Click here for more articles about other treatments for epilepsy.Click here for more articles about brain science including genetics.