Familial Progressive Myoclonic Epilepsy (FPM1) is a rare genetic disorder characterized by a combination of progressive myoclonus (involuntary muscle contractions) and epilepsy. It belongs to a group of disorders known as progressive myoclonus epilepsies, which are characterized by the progressive worsening of symptoms over time.
FPM1 is predominantly an inherited disorder, meaning it is passed down through families. It is associated with mutations in specific genes, such as the cystatin B gene (CSTB) and the neuronal ceroid lipofuscinosis gene (PPT1). These mutations lead to abnormal functioning of certain proteins in the brain, resulting in the characteristic symptoms of the disorder.
The main symptom of FPM1 is myoclonus, which involves brief, shock-like muscle jerks that can affect various parts of the body. These myoclonic jerks typically increase in frequency and severity as the disease progresses. In addition to myoclonus, individuals with FPM1 also experience various types of seizures, such as generalized tonic-clonic seizures or absence seizures.
Other common features of FPM1 include cognitive decline, speech difficulties, coordination problems, and visual impairment. Symptoms typically begin in childhood or adolescence and worsen gradually over time, leading to significant disability in adulthood.
Currently, there is no cure for FPM1. Treatment mainly focuses on managing symptoms and minimizing seizures through the use of antiepileptic drugs. Supportive therapies, such as occupational therapy and speech therapy, may also be beneficial in managing the cognitive and motor symptoms associated with the disorder.
