Myoclonic encephalopathy CHD2 (CHD2 myoclonic encephalopathy) - Gen CHD2
Myoclonic encephalopathy CHD2 is a disease characterized by epilepsy, encephalopathy and intellectual disability. Epilepsy usually begins in childhood, between the ages of 6 months and 4 years. Each individual can manifest a variety of types of seizures. The most common are myoclonic seizures, involving involuntary muscle spasms. Other types of seizures include atonic seizures, partial or complete loss of consciousness, febrile convulsions and tonic-clonic seizures involving loss of consciousness and muscle stiffness. Some people with myoclonic encephalopathy CHD2 have photosensitive epilepsy, in which episodes are triggered by flashing lights. Some people with miocólica CHD2 encephalopathy suffer from a type of seizure called myoclonic-atonic crisis absence. Epilepsy may worsen, leading to prolonged episodes of seizure activity lasting several minutes. Seizures associated with encephalopathy miocólica CHD2 are called refractory because they usually do not respond to therapy with antiepileptic drugs.
Other signs and symptoms include myoclonic encephalopathy CHD2 intellectual disabilities and delayed speech development. Rarely, people may exhibit developmental regression after the onset of epilepsy. Some people with miocólica encephalopathy CHD2 autism spectrum disorders manifest. In some cases, areas found with atrophy of brain tissue.
This process is due to mutations in the gene CHD2 (chromodomain helicase DNA binding protein 2), located on the long arm of chromosome 15 (15q26.1), which encodes Chromodomain helicase with binding 2. This protein is found in cells throughout the body and regulates gene expression through chromatin remodeling. The chromatin structure is reshaped to alter the way that DNA onstituye. Although the exact function of the protein in the brain is unknown, it is believed that the protein may be involved in regulating the development and functioning of neurons.
It described at least 30 CHD2 gene mutations in people with myoclonic encephalopathy CHD2. Approximately half of these mutations eliminate DNA fragments CHD2 gene. These and other gene mutations CHD2 inhibit protein synthesis Chromodomain helicase binding 2 or result in the synthesis of a nonfunctional version of the protein. Consequently, chromatin remodeling and gene expression regulated by this protein is interrupted. It is unclear why CHD2 gene mutations appear to affect only neurons in the brain or how result in signs and symptoms of encephalopathy miocólica CHD2.
Myoclonic encephalopathy CHD2 is considered a process autosomal dominant, which means that a copy of the altered gene in each cell is sufficient to express the disease. This process is due to new mutations in the gene that occur during the formation of reproductive cells or early embryonic development. These cases occur in people with no history of disease in your family.
Tests in IVAMI: in IVAMI perform detection of mutations associated with myoclonic encephalopathy CHD2, by complete PCR amplification of the exons of the gene CHD2, and subsequent sequencing.
Samples recommended: EDTA blood collected for separation of blood leukocytes, or impregnated sample card with dried blood (IVAMI may mail the card to deposit the blood sample).