King’s College London Identifies Impulsivity-Linked Genes in Epilepsy
The new study, published in Nature Genomic Medicine, analysed DNA from individuals with Juvenile Myoclonic Epilepsy. It is the first to screen for and identify genetic variants associated with impulsivity in a neuropsychiatric disorder.
Juvenile Myoclonic Epilepsy is a common type of epilepsy characterised by several types of seizures starting in adolescence. This type of epilepsy can be difficult to treat due to resistance or intolerance to antiseizure medication, which is seen in about 50% of women with JME. There is therefore a need to improve treatment options in JME.
The study examined 376 samples collected through the BIOJUME (Biology of Juvenile Myoclonic Epilepsy) consortium across 10 countries. Individuals self-reported elevated impulsivity, a behavioural trait demonstrated by poor planning, risky, or inappropriate behaviours that can result in undesirable consequences.
Impulsivity has previously been linked to JME as well as attention-deficit hyperactive disorder (ADHD) and bipolar disorder. In JME specifically, impulsivity has also been associated with an increased frequency of seizures.
Genome-wide screening identified SLCO5A1 as a main gene associated to impulsivity. This gene has not been studied extensively in relation to either impulsivity or epilepsy. However, knockout of the equivalent gene in fruit flies results in seizure-like events and overactivity in the organism.
Researchers found that SLCO5A1 interacts with other genes that are responsible for “synapse assembly”, a crucial process for neurons to form connections with each other. Alterations in this process has been linked to epilepsy and other neurodevelopmental disorders.
This discovery gave promising evidence to assess impulsivity in neuropsychiatric disorders. It also uncovered the link between impulse control and seizure control, which may have implications for new treatments.
We believe that this finding indicates that assessing impulsivity in individuals with Juvenile Myoclonic Epilepsy may improve clinical assessments and treatment selections. This is an important step towards personalised medicine in neuropsychiatry.
Professor Deb Pal, the Joint Senior Author of the study