What causes Lafora disease ?
What causes Lafora disease? Most cases of Lafora disease are caused by changes (mutations) in either the EPM2A gene or the NHLRC1 gene. These genes encode proteins that play a critical role in the survival of nerve cells (neurons) in the brain. Although the proteins are thought to have many functions in the body, one important role is to help regulate the production of a complex sugar called glycogen (an important source of stored energy in the body). Mutations in the EPM2A gene or the NHLRC1 gene interfere with the production of functional proteins, leading to the formation of Lafora bodies (clumps of abnormal glycogen that cannot be broken down and used for fuel) within cells. A build up of Lafora bodies appears to be especially toxic to the cells of the nervous system and leads to the signs and symptoms of Lafora disease.