SNP Shot: Genomic Insights

Lafora progressive myoclonus epilepsy is a neurological disease marked by recurring epileptic seizures and a progressive decline in cognitive abilities. Typically, the symptoms begin in late childhood or adolescence and gradually worsen.

Myoclonus refers to sudden, involuntary muscle jerks or twitches. These can affect a specific area or the whole body. Myoclonus episodes can happen even when a person is resting, and they are often intensified by movement, excitement, or exposure to flashing lights (photic stimulation). In the advanced stages of Lafora progressive myoclonus epilepsy, myoclonus can become continuous and widespread.

Individuals with Lafora progressive myoclonus epilepsy commonly experience several types of seizures. Generalized tonic-clonic seizures, also known as grand mal seizures, involve the entire body, causing muscle stiffness, convulsions, and a loss of consciousness. Occipital seizures can also occur, resulting in temporary blindness and visual hallucinations. As the disease progresses, the seizures become more severe and harder to control. A dangerous condition called status epilepticus, characterized by continuous seizure activity lasting for several minutes or longer, can also develop.

Around the onset of seizures, cognitive function begins to deteriorate. Early signs and symptoms include behavioral changes, depression, confusion, and difficulty speaking (dysarthria). As the disease progresses, a persistent loss of cognitive function (dementia) impairs memory, judgment, and thinking. By their mid-twenties, affected individuals lose the ability to perform everyday tasks and eventually require full-time care. Survival after the initial appearance of symptoms in individuals with Lafora progressive myoclonus epilepsy is generally limited to approximately 10 years.

Inheritance:

The inheritance pattern for this condition is autosomal recessive. This means that both copies of the responsible gene in each cell must contain a mutation for the condition to manifest. The parents of an affected individual each carry one copy of the mutated gene, but they usually do not exhibit any symptoms of the condition themselves.